Down Syndrome


This week I will be discussing a genetic disorder referred to as Down Syndrome. Down syndrome is a chromosomal disorder that is seen worldwide. Down syndrome is the result of an extra copy of all or part of the 21st chromosome. With 6000 babies are born with down syndrome each year, the number of individuals with down syndrome are increasing rapidly. There are over 400,000 people in the US alone who are currently living with down syndrome

Before I continue, I would like to provide some background information. Every cell in the human body contains genes that are grouped along the chromosomes in the cell’s nucleus. In a normal individual there are 46 chromosomes in each cell, 23 of the chromosomes are inherited from a mother and the other 23 chromosomes are inherited from a father. When an individual has down syndrome, they have an extra full or partial copy of chromosome 21. So instead of having 46 chromosomes, they have 47. The extra full or partial chromosome is caused by an error in cell division called nondisjunction.

In the past, it has been stated that Down Syndrome is predominantly caused by maternal genes. Some may be opposed to this statement; however, it is supported by the available statics. In more than 90% of syndrome cases, the extra copy of chromosome 21 comes from the mother in the egg. In about 4% of the cases, the father provides the extra copy of chromosome 21 through the sperm. In the remaining cases, the error occurs after fertilization, as the embryo grows.

The most influential maternal characteristic that is associated with producing a child who suffers with down syndrome is age. The likely hood of having a child who has down syndrome increases as women age. At the age of 25 the likelihood is 1 in 1300; at age 30 the likelihood is 1 in 900; at the age of 35 there the likelihood is 1 in 350; at age 42 the likelihood is 1 in 55; and at 49 the likelihood is 1 and 25.

Individuals who have down syndrome experience very distinctive symptoms as well as secondary infections due to being immunocompromised. Down syndrome causes a distinct facial appearance, intellectual disability, developmental delays, heart disease, and several more. Due to being immunocompromised people with down syndrome are at a greater risk for several health problems and conditions than those who do not have down syndrome.

There is no single, standard treatment for down syndrome. Treatments are based on each individuals specific physical and intellectual needs as well as their strengths and limitations. Early intervention programs which consist of a team composed of several therapist and special educators who can treat a child’s specific condition. With the proper care and support, one can live a fully functioning life even if they do have down syndrome.






Comments

  1. Caitlyn GaffneyOctober 25, 2017 at 7:28 PM

    Wow I had no idea that there were so many people living with down syndrome. I remember briefly talking about this genetic disorder, but none of my professors ever went into too much detail. Your blog taught me a lot! Great post!

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