Genetics

What is Tay-Sachs Disease?

Tay-Sachs disease is an autosomal recessive fatal genetic disorder that destroys nerve cells in the brain and spinal cord progressively Which is also known as GM2 gangliosides or hexosaminidase-A (Hex-A) disorder. According to literature the absence of Hex-A, a fatty substance, or lipid, called GM2 ganglioside will accumulate abnormally in cells, especially in the nerve cells of the brain.

The disease was named by two doctors working independently; Warren Tay (183-1927) British ophthalmologist, who in 1881 described a patient with cherry-red spot on retina of the eye.

And Bernard Sachs (1858-1944), an American neurologist whose spend several years later provided the first description of the cellular change in Tay-Sachs, moreover he identify (acknowledge) the familial nature of the disease, and, by observing several cases he noted that the higher occurrence of Tay-Sachs disease in Jews of eastern and central European descent, but many cases now occur in people from different ethnic backgrounds.

Hex-A Deficiency Discovered and Gene Identify:

In August 1969 both Dr. Shintaro Okada and Dr. Johns. O’Berien announced the discovery of the Hexosaminidase A deficiency in Tay-Sachs. About two years later in May 1971 the first screening of the Tay-Sachs disease took place in Bethesda, Maryland. The gene that causes the disease was recognized in late 1980’s and by the mid-1990’s, more than 75 different mutation had been identified, until this day there are over 100 mutations been reported from the ethnic group.

Tay-Sachs and Genetics

Basically, Tay-Sachs disease genetically inherited which causes a neurodegenerative disorder. Individuals who affected from this disease experience abnormal brain development that gets progressively worse. The consequences are a life expectancy of no more than five years of age due to complexity related to this disorder such as (pneumonia)

Tay-Sachs disease is inherited from one’s parents, who do not show any symptoms. The disease(the condition) is an autosomal recessive disorder. Put another way, the parents have a defective gene but because the gene has not been expressed, they do not have symptoms. However, if both parents who have a defective gene produce a child, the child ability to inherit both copies of the defective gene will be more, one from each parent and what will happen is the child will express the disease.

The defective gene produces a protein, specifically an enzyme called hexosaminidase A (Hex-A) which is located 15q23, which is the long (q) arm of chromosome 15 at position 23 as it shows in (Figure 1).

(Hex-A) is essential for speeding up a certain biochemical reaction as its been mentioned before the enzyme disorder leads to the accumulation of a compound called ganglioside GM2, a fatty lipid or substance found enriched in nerve cells of the brain. This compound accumulation in the brain leads to the deterioration(failure) of both physical and mental development.

Muscular degeneration will impact children who over the time they will become blind, deaf, and unable to swallow any food which could lead to complete paralysis. The main reasons why Tay-Sachs become worse more and more with age because the compound retain accumulating over the time. This fatty substance can even accumulate during pregnancy, where the first destructive effect take place, although the clinical significance dose not appear until the first few months after birth.

Symptoms:

Tay-Sachs symptoms disease usually start when a child is 3 to 6 months of age which is heartbreaking. Around this time, the slowing in baby developments and the muscles weaken will be noticed. Progressively, the disease will cause more symptoms in infants such as :

• A loss of motor skills such as sitting, turning over, crawling basically losing skills they already learnt.
• A strong reaction to loud noises
• Trouble focusing on objects or even following with their eyes
• Cherry-red spots, which can be seen clearly with an eye examination, in the eyes.

More symptoms will appear by age 2, most children with Tay-Sachs will face more severe issues including :

• Difficulty swallowing
• Breathing problems keep getting worse and worse
• Loss of vision, hearing
• Loos of mental function

Which will eventually lead to paralysis.

How It’s Inherited:

While anyone could be a carrier of Tay-Sachs disease, meaning both parents have a defective copy of the gene (Figure 2), which causing a fault in child’s gene and that prevent the nerves from working properly, the incidence of Tay-Sachs disease is significantly higher between people from eastern European (Ashkenazi) Jewish descent.

Roughly one in every 27 Jews in the United States is a carrier of the disease gene, more over Non-Jewish French Canadians who are living near the St. Lawrence River and in Cajun Community of Louisiana also have a higher incidence of Tay-Sachs, and Old Order Amish community in Pennsylvania, as it has been mentioned before the disease occur in people from different ethnicity so for the general population, about one in 250 people are carriers.

Is There a Cure for Tay-Sachs Disease?

While researchers are still looking for a way to prevent this disease, unfortunately currently there is no cure exists for Tay-Sachs disease however there is kind of treatment but just to make living with it as comfortable as possible. This is called ‘palliative care’, and the process will be, children’s with Tay-Sachs disease will be transferred to a team of specialists, as will help to come up with a perfect plan for those children’s.

Treatments may include:

• Medicines. To help reduce these child’s symptoms, medications will be available for them, including anti-seizure, stiffness medications and Antibiotics to treat any kind of infections like pneumonia if they occur.
• Physiotherapy. Children’s with Tay-Sachs disease are more likely to have a lung infection that cause breathing problems and frequently accumulate mucus in their lunges so to reduce the risk of pneumonia and help with stiffness and improve coughing physiotherapy will be provided.
• Feeding tubes. Children with Tay-Sachs disease may face issue with swallowing or develop respiratory problems by sniffing food or liquids in the lungs while eating. Doctors may require an assistive feeding device to such as gastrostomy to prevent these issues.
• Physical therapy. As the disease progresses, children’s need to keep joints flexible to maintain as much ability to move as possible that’s why physical therapy will be there to help them.
• Support. One of the most important is supporting the family emotionally, seeking out support groups could help them to cope.
• Play and stimulation. It can help those child’s interact with the world through music, scents, and textures.
• Palliative and hospice care. These programs help manage quality of life for children with Tay-Sachs and their families.

How Is Tay-Sachs Diagnosis?

There is a particular way to prevent the community from having babes with Tay-Sachs disease. From a simple blood test can identify Tay-Sachs. Blood samples can be analyzed by ether enzyme assay or DNA studies before the pregnancy it possible to determine whether both or one of the partners are carriers. The gene that cause Tay-Sachs disease. If both partners carry the gene, they might see a genetic counselor to know more about the sequences, then they can decide whether to start a family.

When women is already pregnant, there is two tests that can be performed during the pregnancy period to determine whether the baby will have Tay-Sachs disease.

Chorionic villus sampling (CVS): this test should be done between 10th and 12th weeks of pregnancy by putting a thin needle into belly or places a tube through vagina into cervix, then a small piece will be taken  of the tissue from placenta, the organ that gives the baby nutrients and oxygen. The tissue will be sent to the lab to be tested.

Amniocentesis: this test had to be done bet  ween 15th and 19th weeks of pregnancy, same process as chorionic villus sampling but the sample will be taken from amniotic fluid, the fluid that surrounds the baby in the womb. The fluid will be sent to the lab and tested whether the baby has Tay-Sachs.

Even after giving pregnancy a blood test can show whether the baby got the Hex-A enzyme. Babies who are missing this enzyme have Tay-Sachs also eye exam could determine if the baby has got the disease by looking for a red spot in macula , a part of retina in the back of the eye.

Allergic diseases have been identified to have a genetic link known as atopic where children born into these families will develop an allergic disease. An allergy occurs when the immune system mistakenly perceives that a substance is harmful to the body (Jackson, Marks, May, & Wilson, 2018).

These substances also known as allergens include dust, pollen, dust, or certain medications. HLA genes that are essential parts of the body’s immune system are passed down from parents to their children may cause the production of IgE which are antibodies that protects the body from invaders and harmful substances (Jackson et al., 2018).

Reasons Why the Patient Is Presenting the Specific Symptoms

Every time the body is exposed to the substance, the IgE antibodies detect it and signal the immune system to release histamine into the blood stream that causes allergy symptoms (Ortiz & Barnes, 2015).

Although there is no history of drug or food allergy, the patient reacts to amoxicillin drug through swelling of his tongue and lips and difficulty breathing. The release of chemicals such as histamine causes allergic reactions that affect the throat, lungs, eyes, and gastrointestinal tract (Ortiz & Barnes, 2015). Antibiotics have been indicated to cause allergic reactions by disrupting the gut microbiome.

The Physiologic Response to the Stimulus Presented In the Scenario and Why This Response Occurred

When antigen-presenting cells come into contact with the allergen which is antibiotics, the cells perceive this allergen as an invader. The cells absorb the allergen, process, and display it on the surface of the antigen-presenting cell which migrates to the T-cell (Ortiz & Barnes, 2015). This stimulates the B-cell to produce antibodies that are specific to the allergen.

The B-cells produce IgE antibodies that attach themselves to receptors on the surfaces of mast cells in the blood and mucous surfaces. These cells release inflammatory mediators that include histamine, kinins, or prostaglandins that lead to diverse symptoms (Ortiz & Barnes, 2015).

Cells That Are Involved In This Process

For the allergy to exist, antigen-presenting cells that are present in the mucosal surfaces of the body and the gastrointestinal tract detect the allergen (Bonnelykke, Sparks, Waage, & Milner, 2015). The immune response to an allergen depends on TH1 and TH2. The TH1 release mediators to help the body fight viruses, parasites, or bacteria. The TH2 cells help the immune system to recognize allergens that are perceived as invaders and mount a response against the invader (Bonnelykke et al., 2015).

How Gender affects Allergic Reactions

Men and women are different in diverse perspectives such as the foods they take, sexual hormones, and lifestyles. These influence how immune cells express hormonal receptors (Jensen-Jarolim, 2017). Research indicates women to suffer severe allergic reactions than men.

Gender differences play a role in allergy manifestation. Sex hormones influence the functioning of immune cells affecting the formation of allergies. IgE levels are higher in women compared to women which means that women overreact to allergens (Jensen-Jarolim, 2017).

References

• Bonnelykke, K., Sparks, R., Waage, J., & Milner, J. D. (2015). Genetics of allergy and allergic sensitization: common variants, rare mutations. Current opinion in immunology, 36, 115–126. https://doi.org/10.1016/j.coi.2015.08.002
• Jackson, M., Marks, L., May, G., & Wilson, J. B. (2018). The genetic basis of disease. Essays in biochemistry, 62(5), 643–723. https://doi.org/10.1042/EBC20170053
• Jensen-Jarolim, E. (2017). Gender effects in allergology – Secondary publications and update. The World Allergy Organization journal, 10(1), 47. https://doi.org/10.1186/s40413-017-0178-8
• Ortiz, R. A., & Barnes, K. C. (2015). Genetics of allergic diseases. Immunology and allergy clinics of North America, 35(1), 19–44. https://doi.org/10.1016/j.iac.2014.09.014

The topics that pertain most to my life are behavior genetics and predicting, sleep deprivation/ sleep disorders, tolerance and addiction, stability vs. change, and stress/ basic concepts. These topics bring me interest because I have opinions on them. I want to share what I think and how they affect others and/or myself. I can think of myself in all of these topics because of how I can relate to them.

The first topic I want to acknowledge is behavior genetics and predicting individual differences. Behavior genetics are the traits and behaviors you can get genetically passed down from your family members. People can try to predict how someone’s personality will turn out by looking at their parents and/or past generations.

This method of thinking doesn’t always turn out to be accurate. “A study of 500 boys with the genotype of MAOA low combined with the exposure to childhood maltreatment was shown to see if it increased the levels of antisocial behavior” (Stone, 2003).

The results showed that to some extent genetics can effect if a child grows up with certain behavior traits (Stone, 2003). These studies show that genetics do have an affect if a person acts a certain way. With more research we might be able to figure out who important people will be in the future.

A big question with determining people’s genetics to there personality is if it is even plausible to go by their genetics. There are cases in which genetics can be wrong. If we go by genetics then someone can be wrongly accused for actions that they did not commit or might be seen as someone they are not.

“Social influences were partially dependent on 5httlpr genotype such that possession of more 5httlpr’s alleles were associated with stronger susceptibility to the influences of school-level smoking and drinking patterns” (Daw et al, 2013). This information shows that most substance use is mainly a person’s choice and their behaviors come from the environment they’re in and not by the genetics they have.

I can relate this back to my life because my family has a long history of mental disorders that have been passed down. I have always wondered if I got my disorders from my genetics or if they’re something that my environment has caused. When predicting who someone will become, often times you look to who there parents are. Past genetics can show you what disorders and mental illness a child might have but a child’s actions are not caused by genetics.

The next topic that interests me is sleep deprivation/ sleep disorders. Sleep deprivation is not being able to get a good amount of sleep and in it can possibly lead to disorders. “A sleep foundation study showed that 40% or fewer adults get less than 7 hours of sleep a night” (Choo et al, 2005).

Different things like phones, television, and light can keep a person awake even after everything has been turned off. If you can get a healthy amount of exercise and turn off all electronics when you are going to bed, it can help with the amount of sleep you get as well as the quality of it.

Evidences show that sleep is essential for proper brain performance and everyday actions; as well as learning and long-term memory which pertain the most to sleep (Bibi et al, 2018). Without the suitable amount of sleep, you will not be able to function the best you can. You become sloppy and disorganized with not only your appearance but your thoughts as well. Sleep deprivation can also cause sleep disorders. Sleep disorders affect a lot of the American population.

Disorders exist when there is a lower quality of sleep which leads to impaired functioning or dangerous sleepiness (Buscemi et al, 2006). Sleep disorders can come from genetic problems or poor lifestyle habits, both of which are just as hard to cure. According to Buscemi 2006, alternative medicines can be used to help with sleep disorders. One of the most common medicines being melatonin.

Melatonin is an over the counter sleep medicine to help with the length and quality of sleep. In most cases melatonin helps with sleep, but it is not for everyone. Sleep disorders such as insomnia, sleep paralysis, and night terrors, can lead to daytime sleepiness and an increase in daily accidents (Shapiro and Dement, 1993).

Without a good amount of sleep, you can be at risk of these disorders. In my family, my mother takes prescription medicine to be able to fall asleep and stay asleep. I have always had a hard time falling asleep and staying asleep. I took melatonin for two years until it stopped helping my sleep schedule. Once I realized that my sleep wasn’t easy to fix, I thought about my mother’s issues and how it could have been genetically passed down to me. By understanding her struggles, I was able to figure out my own and correct my sleep schedule making me a happier person all around.

My third topic is tolerance and addiction. In this day and age, it is very easy for people to become addicted to something. The availability to get things that aren’t necessarily good for you has become extremely effortless. Since things are so accessible, people are able to get them in abundance.

When this happens, the tolerance for any drugs or substances become very high making people need more to buy and feed their addiction. Drug tolerance is closely related to withdraw and craving symptoms. When there is a craving, you feed into the addiction making your tolerance become higher (Siegel, 1999). Tolerance builds when a person doesn’t receive the same effects from a drug and requires more of it.

The more you give in, the higher your tolerance becomes because your body needs more and more of that substance to get the same affect. “Several studies suggest that drug tolerance makes drug abstinence more difficult and causes behavioral withdrawal symptoms” (Trivedi and Deth, 2015).

Tolerance and addiction go hand and hand, because of if one increases, it causes the other to increase as well. According to Trivedi 2015, depending on how high your drug tolerance is, it can change the outcome if your recovery will be successful or not. People can get addicted to the positive responses they get from what they are consuming.

When a person feel like they can not live without it, it becomes an addiction. Someone can easily become dependent on drugs because of the way it makes them feel and when the addiction starts, it comes with a growing tolerance. I can relate this back to my life because my mother had an addiction to opioid pills. Her addiction was very hard for her to break, so she continued to use them because they would make her feel like she needed them.

When taking opioids, they make you feel like you are in pain when in actuality you are not. This caused her to take more causing her to build a high tolerance for them. She later found out that she was taking way more than the average person could even take. Once she realized she was taking an unhealthy amount, she knew she had to fix the problem the pills created. It is a fight for her everyday because of an addiction to opioids and the tolerance caused.

Another topic I wanted to cover is the stability vs. change debate. The stability vs. change debate states that you either believe that you stay the same person throughout your whole life, or you believe that your personality can change over the years. Most studies suggest that someone’s personality doesn’t change that much from adolescence to adulthood but individual differences in personality stability can (Clausen and Jones, 1998).

Most of the time if a person is more self-realized at a young age, they have a greater chance of being on the stability side. Some things that effect if a person is changing or not is the change during maturity from childhood to adolescence and finally adulthood. Another factor is having new responsibilities and understanding that they require different things, along with failures in this department (Clausen and Jones, 1998).

These factors are something to keep in mind when considering if someone has changed throughout their life. Most people need some type of difficulty and gratification to make them go through a personality change. Personality stability is mostly studied in adults because your personality is said to mostly form between ages 20-30 (Blantny, 2007).

This research has put scientist behind because they should have been looking at all ages to figure out if stability and change happen throughout someone’s life (Blantny, 2007). I personally believe that people change throughout their entire lives. I have changed a lot just from my early high school years to the end of high school. From going though different struggles and successes in my life, I became very responsible and self-realized very fast.

This made me change a lot because I had to grow up fast to meet the needs of my situation. From these events in my life, I couldn’t stay the same. Being forced to change gave me a sense of responsibility. For these reasons in my personal life, I believe that people change as they go through life.

The last topic that I would like to talk about is stress and its basic concepts. Stress is something that many people in the world deal with. Depending on certain events in your life, it can determine if you’re more susceptible to stress or not. Different illnesses such as depression and anxiety can contribute to stress. It is not easy to deal with stress since different people react differently to given methods (Strumska, 2013).

Furthermore, stress can be contagious just like if someone is in a bad mood it could put you in a bad mood. When someone is feeling massive amounts of stress, it can be spread onto someone else as well. According to Strumska 2013, stress refers to a condition in which mental tension exceeds the specified amount level of functioning. Stress can actually make a condition you have worse. According to Liu et al, 2017, studies show that stress can increase symptoms of patients with certain illnesses.

Experiences of stress has been known to diminish health and adjust someone’s well-being (Liu et al, 2017). If you are successful in coping with stress, it can induce more motivation and positivity. Common ways of coping with stress are medication, exercise, and meditation. Certain methods work for different people. Meditation might not work for everyone who tries it because of different body types. According to Liu 2017, prolonged stress results in exhaustion of bodily resources.

This is why research on how individuals respond to stress is so emphasized. This shows up in my life a lot because of my stressful nature. Even when things could be going completely adequate in my life, I could still find something to stress about. My family has had a long history of anxiety and stress so it has lead me to believe that some of my habits could be genetic.

I was on stress reducing medication and it helped me cope with a lot of my stress, but it took many years to be able to find the right medication. Different stress coping mechanisms work for me but maybe not as well for my relatives. In all, stress is something I will always live with but as long as I try to cope with it, I can overcome it.

In conclusion, I am able to relate to these topics because they each played a role in my life. In reality, we all face a lot of these problems daily and work towards understanding them. Without knowing the research behind a problem or idea, there is no way to fix it. These topics have helped me to better understand things about myself and my family, as well as how to solve some of the long-lasting obstacles we all deal with.

References

• Bibi, z. J., Vaezi, G., nasehi, m., seyed-, A. H., & Mohammad-Reza Zarrindast. (2018). Critical role of CA1 nicotinic receptors on memory acquisition deficit under induction of total sleep deprivation and REM sleep deprivation. International Clinical Neuroscience Journal, 5(1), 11-20. Retrieved from http://proxy004.nclive.org/login?url=https://search.proquest.com/docview/2170393884?accountid=13993
• Blatný, M. (2007). ON PERSONALITY STABILITY AND CHANGE: MAIN RESULTS OF BRNO LONGITUDINAL STUDY ON LIFE-SPAN DEVELOPMENT. Ceskoslovenska Psychologie, 51, 37-49. Retrieved from http://proxy004.nclive.org/login?url=https://search.proquest.com/docview/235721964?accountid=13993
• Buscemi, N., Vandermeer, B., Hooton, N., Pandya, R., Tjosvold, L., Hartling, L., . . . Baker, G. (2006). Efficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction: Meta-analysis. BMJ : British Medical Journal, 332(7538), 385. doi:http://dx.doi.org/10.1136/bmj.38731.532766.F6
• Choo, W., Lee, W., Venkatraman, V., Sheu, F., & Chee, M. W. L. (2005). Dissociation of cortical regions modulated by both working memory load and sleep deprivation and by sleep deprivation alone. NeuroImage, 25(2), 579-587. doi:http://dx.doi.org/10.1016/j.neuroimage.2004.11.029
• Clausen, J. A., & Jones, C. J. (1998). Predicting personality stability across the life p: The role of competence and work and family commitments. Journal of Adult Development, 5(2), 73-83. doi:http://dx.doi.org/10.1023/A:1023038410560
• Daw, J., Shanahan, M., Harris, K. M., Smolen, A., Haberstick, B., & Boardman, J. D. (2013). Genetic sensitivity to peer behaviors: 5HTTLPR, smoking, and alcohol consumption. Journal of Health and Social Behavior, 54(1), 92-108. doi:http://dx.doi.org/10.1177/0022146512468591
• Shapiro, C. M., & Dement, W. C. (1993). ABC of sleep disorders. impact and epidemiology of sleep disorders. BMJ : British Medical Journal, 306(6892), 1604. doi:http://dx.doi.org/10.1136/bmj.306.6892.1604
• Siegel, S. (1999). Drug anticipation and drug addiction. the 1998 H. david archibald lecture: (alcoholism and drug addiction). Addiction, 94(8), 1113-24. Retrieved from http://proxy004.nclive.org/login?url=https://search.proquest.com/docview/199659033?accountid=13993
• Stone, R. D. (2003). The cloudy crystal ball: Genetics, child abuse, and the perils of predicting behavior. Vanderbilt Law Review, 56(5), 1557-1590. Retrieved from http://proxy004.nclive.org/login?url=https://search.proquest.com/docview/198850396?accountid=13993
  Strumska-Cylwik, L. (2013). STRESS AND COMMUNICATION (I.E. ON STRESS IN COMMUNICATION AND COMMUNICATION UNDER STRESS). International Journal of Arts & Sciences, 6(3), 419-441. Retrieved from http://proxy004.nclive.org/login?url=https://search.proquest.com/docview/1496695252?accountid=13993
• Liu, J. J. W., Vickers, K., Reed, M., & Hadad, M. (2017). Re-conceptualizing stress: Shifting views on the consequences of stress and its effects on stress reactivity. PLoS One, 12(3) doi:http://dx.doi.org/10.1371/journal.pone.0173188
• Trivedi, M. S., & Deth, R. (2015). Redox-based epigenetic status in drug addiction: A potential contributor to gene priming and a mechanistic rationale for metabolic intervention. Frontiers in Neuroscience, doi:http://dx.doi.org/10.3389/fnins.2014.00444

Gene is a basic physical and functional unit of heredity and is made up of DNA. It occupies a fixed position on a chromosomes, which are the sets of genes in the body. They determine how a body forms and functions during pregnancy and after the birth. Hence, determining all the physical, mental and biological traits. Typically, a normal cell has 46 chromosomes. People with Down syndrome are born with extra copy of chromosome 21. This phenomena is called “Trisomy 21”. Though this occurs only 95% of the time. (Walsh, 2018) It is a lifelong condition, having this extra copy causes various range of issues both physically and mentally.

The main cause of trisomy is an abnormal cell division during the development of sperm or egg cell. At conception, a new cell if formed that receives a copy of each chromosome i.e. from a sperm and egg cell. Eventually this cell further grows and divides into many cells to form a fetus and then a human body. However, in a cell where trisomy occurs there forms total 47 chromosomes. Sometimes translocation happens, in which, an extra piece of chromosome 21 gets attached to another chromosome. Most people with Down syndrome has a genotype of 47+2. While, phenotype varies in a great extent. (Walsh, 2018)

Prevalence: Down syndrome is the most common genetic disorder throughout the world. It has been stable in last decade in Canada, averaging 15.8 per 10,000 total births, between 2005 and 2013. It occurs approximately 1 in 750 babies. The rate among stillbirths is 31.2 in 1000. In live birth is 13.5 in 10,000 between years 2005-2013. The figure illustrates Down syndrome rates by outcome in Canada including rates per 1000 stillbirths and 10,000 live births, also 95% confidence interval. (Morris, 2002)

(Morris, 2002)

The Research also says that risk of Down syndrome increases if a mother delivering the baby is above 35 years of age. The highest percentage is 29%. The following figure illustrates proportion of live births and Down syndrome births within each maternal age category in Canada. (Cocchi, 2010)
(Cocchi, 2010)

Symptoms: People with Down syndrome have various physical features that includes:

• Small head and ears.
• Swelling tongue.
• Short neck.
• Inclined eyes (usually upwards).
• Atypically formed ears.
• Poor muscle co-ordination.

Some of the medical implications that people with Down syndrome faces are: heart defects, hearing loss, leukemia, obesity, Alzheimer’s disease, sleep disturbances, dislocations, urinary tract infections, skin infections, and respiratory problems. (Karen, 2017).

Children with Down syndrome faces some difficulties in day to day life. Sometimes, both in home and school settings. Some of the Health Concerns that affect the learning of the student with Down syndrome includes: weak auditory memory, concentration issues, limited understanding, hearing problems, and visual problems, speaking problems, gross and fine motor difficulties, and difficulty in generalizations. Students with Down syndrome have heart, ear, nose, throat, and sleep difficulties even. Sleep intolerance can cause anxiety, hyperactivity, tiredness and lethargic.

The accommodations and modifications may be implied to the curriculum of a student with Down syndrome.

1) Weak Memory: Students with Down syndrome often have short term memory difficulties. This leads to a huge loss in their learning process. As they are not able to match the pace with their other fellow peers. But it doesn’t mean it will affect their will to learn. The following points might prove effective to prevent this difficulty:

• A teacher may allow more time to learn.
• More practise of generalizations.

2) Hearing and Vision problems: This is the most common difficulty faced by people with Down syndrome. Around 80% people with Down syndrome faces this problem. The following tips can be useful to overcome this aid:

• A student can be placed In front of the class.
• Visual aids can be very effective. (E.g. write on blackboard).
• By using larger fonts and bold sentences.
• Repeating questions and using clear, concise and loud voice.
• Including electronic gadgets like iPad, pc.

3) Gross and fine motor skills: Many students with Down syndrome faces difficulty in performing these skills, but, following points may enhance these skills:

•  Every student should have comfortable working space. Especially for student with Down syndrome, as such to support their stability.
•  Provide proper back support for long periods.
•  Proper space for their wheelchairs and personal supporting devices.
•  Gym class should have some equipment’s which may be proven useful and which maybe easy accessible to students with Down syndrome.

4) Speaking: Students face difficulty in speaking due to low muscle tone and jaw movements. Teachers can do following points to help student with speech difficulties:

1.  By using simple questions.
2.  By including them in almost every class discussion.
3.  Occupational therapist may provide help to the student.
4.  Sign language may be included in their IEP/ Curriculum.

5) Concentration issues: Students with Down syndrome may have ADHD. Hence, proper attention need to be provided to them. A teacher can do the following steps;

•  They can use more colourful and interesting books to keep them engaged in studies/learning.
•  They can use their favourite stories or movies to read or play in some spare time

There are some common myths about people with Down syndrome including;

• People with Down syndrome must be educated in segregated classrooms: They have full right to be a part of mainstream classrooms and learn what they wish to.
• They are always happy: They do have feelings like any other human beings. They do get hurt by negative experiences and happy with positive.
• They are full retarded: Which again a false statement. Most people with Down syndrome have their IQ’s fall under moderate rates.

Despite many issues of reliability of LCN analysis, this technique is already well established. The question in validity of LCN typing lies not with the technique itself but how DNA is handled to avoid contamination. Several methods have been reinforced in order to increase reliability of LCN typing. There are: Increasing PCR cycle numbers to achieve sensitivity enough for right results; Strengthening the fluorescent dye signal; using the higher purity formadine in a sample preparation for electrophoresis; negative control are used on every step to show absence of contamination; the results are compared against the stuff database. An addition, all practices reduced a lab contamination by: using hermetic rooms; very sterile labs; changing clothing at every sample during analysis; materials and instruments are free of other DNA; lab equipment treated with bleach and irradiated with UV light; post PCR cleaning. These rules, also, apply during gathering and packaging touch DNA at crime scene and transportation. Hence, the routine procedure designed with minimum risk of data to be failed. Moreover, DNA evidences are typically meaningful by statistics. The most common statistic is Random Match Probability(RMP) that highly impressive because of billions and trillions estimates. Even in cases of mix DNA, the using of combined probability of inclusion and exclusion are still remain reliable. In that case, most lab scientist endorse 2-3 analysis of LCN typing, and allele must be observed twice, so when more replicates show the same allele, the more validate result is. Even more, the high trained forensic stuff are well familiar with the interpretation methodology of data and statistics that give additional confidence in validity. Altogether, I argue in favor of the value of LCN evidence presented in this Court. The tragic terrorist attack in Omagh, Ireland in 1998 raised the question of reliability of LCN typing for the first time.

The penetrator was arrested, and then released due to lack of validity of how LCN testing was provided. Criticism named this method as “robust” and “fit to purpose”. Hence, LCN evidence presented today in Court should not be accepted as evidence due to technique causing many debates and lack of reliability of this test. There are some flows. ​Sensitivity​ of touch DNA and Low Template DNA can lead to higher possibility of errors. For example, the sensitivity increases the risk of ​contamination​ of DNA which is a pretty small molecule(less than 100-200 bp), and phenomena as allele ​drop-in ​when allele is not part of the typing profile is seen. We know that LCN requires more numbers of PCR cycles from 28-30 to 34. Rising PCR cycles creates allele drop-in as random event which may not be very supportable. In addition, after a crime, the contamination can occur on each step during detecting, gathering and transferring LCN by investigators, and accepting by lab workers, their efforts on extraction and amplification in PCR machine. The very sterile environment and accuracy have to be keeped on the each step because LCN(or LTDNA) may be contaminated even by touching a test equipment by skin, or breathing on a sample of DNA. Environmental conditions such as temperature and humidity are, also, important factors that affect the final results. Moreover, the data interpretation is more complicated due to ​stochastic threshold ​that more noticeable during amplification. There are possibility of allele ​drop-out​ and ​peak imbalance​ to be occurred when peaks from heterozygote is imbalancing, and a heterozygote appears as a homozygote. Further, sometimes it is hard to find out how individual’s DNA came because the individual could not be present at scene at all. Tiny amounts of DNA can be passed through handshake, or in a high speaking area. Hence, the presence of a suspect’s DNA does not mean that a suspect was present at crime scene. This situation gives a rise to the problematic interpretation of a ​mix DNA​. Consequently, we should see all evidences, as a whole picture, and the data has to be interpreted with caution and all knowledge in order to be accepted.

Previous studies have shown that F1 hybrid females between koi carp (Cyprinus carpio) and goldfish (Carassius auratus) produce diploid eggs due to a transformation of meiosis. Crossing F1 hybrid females with koi results in backcross triploid hybrids with two haploid chromosome sets of koi, and have one set of goldfish (FBK), while crossing these females with goldfish produces triploids with two sets of goldfish and one set of koi (FBGF). The goal of this study was to evaluate the reproductive ability of both variants of triploids. Some triploid hybrid females of both variants produced eggs after injection of CPE. Eggs were fertilized with sperm from diploid males of parental species (koi and goldfish). Progenies obtained from FBGF females did not survive past one month, and their ploidy has not been analyzed. Progenies obtained from FBK females also had low survival; nonetheless about 1,000 5-month-old juveniles were obtained. Approximately 350 juveniles were analyzed for ploidy by analysis of DNA content in erythrocytes. Analyzed juveniles had an average ploidy of approximately 2.5n, with the majority of values being within the range of 2.3n-3.0n. Since aneuploid fish have in their genomes one haploid set from parental males, this data indicate that FBK females produce aneuploid eggs with a ploidy range of 1.3n-2.0n, and a modal ploidy of approximately 1.5n.

Aquatic vegetation is necessary for a healthy ecosystem by providing several services such as: habitat for organisms, breeding territory for fish, a source of food, improved water quality, withholding sediments, and several more. An excess of aquatic vegetation can however be disadvantageous by making it more challenging to harvest fish, and by having a negative impact on biodiversity, water quality, and on recreation via decreased maneuverability for boats. Invasive aquatic weeds are a significant problem globally with large financial implications; the United States alone is estimated to spend over 100,000 million dollars annually on aquatic weed control. Herbicides, manual removal, and biological control are all options for the removal of aquatic weeds. Manual removal of aquatic weeds is not ideal due to being labor intensive, especially in large bodies of water, and is not a long-term solution. Herbicides are the most commonly used option for removal of aquatic weeds, and can be a fast and effective method contingent on the proper identification of aquatic weed species. It is important to consider that the use of herbicides can negatively impact water quality, and is also not an option when dealing with fish for human consumption. These disadvantages have created the desire for non-chemical treatments of aquatic weeds, which has led to the use of biological control of aquatic weeds.

Biological control is not an immediate fix for aquatic vegetation, but is a more environmentally friendly method in terms of the amount of waste produced. There have been several species of fish utilized for biological control of aquatic vegetation via direct consumption, or by bioturbation effects of foraging behavior. One concern of using biological control is the impact that the introduced species will have on the ecosystem such as outcompeting native species for resources, or unintended hybridization. For this reason, it is desirable that organisms being used for biological control are sterile. It is possible to produce polyploid fish that have additional haploid sets of chromosomes via heat or pressure shock; this allows one to obtain triploid fish that have three haploid chromosome sets and are sterile because of this. Triploid grass carp (Ctenopharyngodon idella) are a popular option for biological control of aquatic vegetation. Another method of producing sterile organisms is hybridization; distant hybridization is when two different species are crossed to generate a new species. Crossing two species with incompatible sets of chromosomes impacts meiosis, and can result in sterility of their offspring.

The occurrence of fertile F1 hybrid females warrants further research on the reproductive capabilities of the triploid progenies originated from them; if it is confirmed that they are sterile then koi x goldfish hybrids can potentially be valuable as biological control. The purpose of this study is to investigate the reproductive capabilities of triploid koi x goldfish hybrid females and results of their crosses with parental species. Crossing these hybrids with their parental species will emulate what could happen in the environment. It is necessary to determine the ploidy of the progenies produced in order to understand the reproductive abilities of the hybrids that produced them. The ploidy of fish can be determined in several ways including: Feulgen microdensitometry, manually counting chromosomes, measuring erythrocytes with coulter counters, gel electrophoresis to observe proteins, and by measuring the DNA content of individual cells with flow cytometry.

The most commonly used method to determine the ploidy of fish is flow cytometry due to its convenience. Flow cytometry has been used since the 1980’s and was initially used for detecting cancerous cells by varying amounts of DNA. Flow cytometry has been used on plants, shellfish, finfish, insects, reptiles, amphibians, phytoplankton, and bacteria. Flow cytometry works by individually shooting particles through a light, and a computer records the disturbance of the light for each particle passing through; the data is then displayed as histograms where different sized particles will show up in different locations. Staining the nuclei with fluorescent dyes to determine DNA content is one of the most common applications of flow cytometry; this technology however is broad and is applied in several other fields when there is need to distinguish subpopulations of a specific type of cell or protein. The methodology for this study is based on quantifying the amount of nuclear DNA in erythrocytes obtained from the fish.

This study was performed at the Aquaculture Research Center (ARC) at Kentucky State University in Frankfort, KY. The fertility of female triploid backcross hybrids was assessed, and those deemed fertile were injected with carp pituitary extract and saline, while all of the male triploid backcross hybrids were injected to induce gamete maturation and spawning. A concentration of 3 mg/kg of the body weight was used. Females received 10% of the total dose 24 hours before spawning, and the remaining 90% 12 hours before spawning. Males recieved the full dosage 18 hours before spawning. Eggs were collected in containers, weighed, and then evenly distributed into bowls. Milt was collected in 30 ml containers. Eggs and milt were then mixed in a bowl with a turkey feather. Two minutes after the fertilization, the eggs were placed in a 1:8 cow milk: water solution in order to reduce adhesiveness of the eggs. After being in the cow milk: water solution for one hour, the fertilized eggs were transferred into McDonald jars to incubate until they hatch.

Hatched larvae were collected in hapas suspended in raceway systems, with a flow of dechlorinated municipal water at approximately 20 °C. Swim-up larvae from the hapas were then relocated into 20 m3 outdoor tanks, supplied from a water reservoir. Progenies remained in outdoor tanks approximately 4-5 months, and were then brought into the Aquaculture Production Technologies building at the ARC. The progeny were placed in indoor recirculating aquaculture systems at approximately 25 °C, and fed a commercial diet. Ploidy was determined by quantifying the amount of nuclear DNA for each fish through the use of flow cytometry at approximately three months after stocking as was done in Delomas et al. (2017), and Warner et al. (2018). Blood was used for this as fish erythrocytes contain nuclei. Fish larger than 25 g had their blood collected from the hemal arch with a 21-gauge needle, and samples were collected in 3.0 ml vacutainer tubes that contained lithium heparin to serve as an anticoagulant. Fish smaller than this had their tails cut and were bled into 1.5 ml microcentrifuge tubes containing a 0.85% NaCl saline solution.

Samples were mixed with a Propidium Iodide Staining Solution (PI), as well as Largemouth Bass (Micropterus salmoides) blood which served as an internal control. Diploid koi blood was used as external controls. 100 µl of PI was first added to each 1.5 ml microcentrifuge tubes. Samples from fish larger than 25 grams had 0.5 µl of bass blood added, and then 0.5 µl of sample blood added. The samples from fish smaller than 25 grams had 4 µl of bass blood added, followed by 4 µl of sample blood. Saline solution was then added to obtain a final concentration of 0.2 µl bass blood/ 100 µl saline. Samples were incubated in the dark at room temperature for 10 minutes, then run on an Accuri C6 (BD Biosciences, CA, USA) flow cytometer for 40,000 events. The ratio of hybrid DNA to bass DNA allows us to calculate the ploidy of the hybrids. Flow cytometry detects the intensity of the emitted fluorescence from the PI stained nuclei as they pass through the machine. Histograms are then generated and contain peaks for both the internal control (bass), and the sample (hybrid). Peaks are isolated from one another using gates, and the mean intensity is then measured. Where FIb is the fluorescence intensity of the bass peak, FIs is the fluorescence intensity of the sample, and Rs is the internal sample ratio. Ratios are obtained which are compared to the external control (diploid koi), in order to determine ploidy levels. The ratio for the control koi is 1.7. The haploid level can be determined by dividing the external control ratio by 2, which results in a haploid ratio of 0.85. The sample ratio is then divided by the haploid ratio, which results in ploidy level of the sample.

Some triploid hybrid females of both variants produced eggs after injection of CPE and yielded progenies with a drastic range of phenotypes and abnormalities when crossed to diploid males of parental species. A total of 344 juveniles obtained from FBK females were analyzed for ploidy. Progenies from FBK females crossed with goldfish males had an average weight of 12.64 g and an average length of 9.53 cm, while those crossed with koi had an average weight of 36.96 g, and an average length of 11.86 cm. All progenies obtained from FBK females had very similar ploidy values so results were pooled. Progeny from these crosses had a ploidy range of 2.3n-4.0n, with the majority being in the range of 2.3n-3.0n, and an average of approximately 2.5n. All progeny obtained from FBGF females did not survive long enough for data on their ploidy to be collected. Goldfish x koi hybrids can potentially be a viable alternative to grass carp for aquatic weed control if they are confirmed to be sterile. Previous studies conducted at the ARC have found that some F1 females were fertile, and produced triploid progeny when crossed to diploid males of the parental species without any treatment to the eggs; quantitatively we are able to confirm that the eggs produced were diploid since the sperm from the diploid males was haploid. The obtained backcross triploids were raised in order to monitor their reproductive capabilities. It was found that a small proportion of the females were fertile and produced aneuploid progenies when crossed with males of parental species.

Progenies obtained from FBK females were majority aneuploid with a mean ploidy of approximately 2.5n. These results were consistent with FBK females crossed with both goldfish and koi males, and show that the eggs produced are approximately 1.5n on average. FBGF females produced eggs, and viable progenies were initially obtained when crossed with both goldfish and koi males. When it was time to collect blood to analyze ploidy of these latter progenies, it was found that no fish had survived. We hypothesize that this mortality is due to the presumed aneuploid nature of these progenies, as well as unusually high temperatures this season. Future work will consist of continuing to monitor the progenies obtained from FBK females in order to observe gamete development, as well as attempting to obtain and analyze progenies obtained from FBGF females. Once the ploidy is analyzed from the latter mentioned crosses, it will be possible to make a better assessment on the reproductive capabilities of goldfish x koi hybrids, and whether or not they will be a feasible option for aquatic weed control.

Amy Harmon is living normal and healthy life with one child in preschool, I assume that she is living a pretty good and pleasant life, still Amy feels attracted to the idea of knowing about her genome and how her health Is evolving through out her life. Amy Harmon Is telling us about the breaking technology with DNA, how It can reveal our future, and tell us if we have any heart disease or cancer, this will let us know our destiny and make us stop the eventually evolving cancer tumor in our body.

These kind of tests only cost about 1,000 $ and one simple salvia sample, and that’s it, Amy tells us that he feels addicted after Just three weeks of daily communion with her genes, it has become a natural daily routine for her, as normal as brushing our teeth every night and morning, Amy checks her account on the site “anadem” the site Is the start up company that deals with DNA and our genomes. His Is also the site Amy uses on a daily basis, actually hours every day, Amy is not only using the site to check out dangers that may appear in the future, but also things like temperament and regular behavior, to check all these DNA strips is like looking under the skin and see the robbers you wont see with your bare eyes, that’s why the DNA test attracts people from every corner of the world. But what would you do when or if a very rare heart disease appears In your system that is Incurable, or something you can’t work your way through, Like a skin disease or eye-problems, cancer, aids or many other dangerous disease.

This is something Amy Harmon has thought about, she wont let her daughter look at her DNA strips, this is because she is afraid to find something that Is incurable and life threatening. Amy Harmon uses a very difficult and adult engage in this article, it makes the content much more serious then If the article was written In a childish way, the difficult words makes us automatically think that this Is a serious case and therefore we don’t doubt the case.

Another thing that makes the reader interested in thing topic, is that Amy uses very personal examples instead of using examples from other peoples life, the article is suddenly very close to our own life, we can understand her issues and we can also understand her addiction to the secret of our body. Many of the risks associated with genetic testing involve the ethical, legal emotional, social, and consequences of the test results.

The result can reveal a very ugly and grim discovery witch not all people can deal with, I thank many people will get storage Trot Walton Day Knolling all sorts AT things Insane you, in worst case it can end in suicide witch would be gruesome. And many people won’t be able to provide the same amount of work if they knew they are carrying a deadly disease with them, this would be fatal for a society, the system would have to ay for all the people who got sick and needed medical treatment and by this I mean mental sick.