Down Syndrome is a genetic disorder. According to NSGC (para.1), the National Society of Genetic Counselors, the human body is made of cells whose nucleus have chromosomes that contain the DNA that carries traits. Each Nucleus normally contains 23 pairs of chromosomes; down syndrome occurs when an individual ends up with an excess of chromosome 21, full or partial. When this chromosomal abnormality due to the extra chromosome occurs, a child is born exhibiting traits characteristic of down syndrome. Many children are born with Down syndrome, since it the most common genetic disorder. Due to progress in medical technology and research, families now have better coping mechanism. Down syndrome is a topic close to my heart since my sister lives with this condition.
There are three types of Down syndrome. The first is Trisomy 21 which according to (Tingey, p 11), happens when the child has “three copies of chromosome 21 (instead of the usual two copies) in all cells” (p. 13). This happens due to abnormal cell division in phase of the development of the sperm cell or the egg cell. The second type is the Mosaic Down syndrome which is not very common. Children who have this form have some cells (not all) with an extra copy of chromosome 21. It is referred to as mosaic due to the mixture of normal and abnormal cells. It happens after fertilization and is due to abnormal cell division. The last one is the Translocation Down syndrome. According to Tangey (p.13), this occurs “when part of chromosome 21 becomes attached (translocated) onto another chromosome, before or at conception.” Such children have the normal number of chromosome 21, but also acquire additional material that comes from the chromosome attached to the translocated one.
Down syndrome has some common general symptoms, however, since each child is different, the presentation of these problems differ from child to child just like in normal children. Intellectual and physical development range from slow to almost normal, for some children. Others are also healthier while others have complicated health problems. Development in children with Down syndrome is generally slow; they attain milestones at roughly double the age of normal children. Laney (P. 13) lists the following common characteristics of Down syndrome:
- Flattened facial outlook
- Small head
- Short neck
- Protruding tongue
- Eyes that slightly slant upward in a way that is not common in the child’s ethnicity
- Small ears which could also have an unusual shape.
- Poor muscle tone
- Broad, short hands with a single crease in the palm
- Short fingers
- Small hands and feet
- Excessively flexible
- Brushfield spots (white spots on the iris of the eye).
- Short in height.
There are no clearly known behavioral or environmental causes of Down syndrome. Inheritance plays a very small part since according to Püschel and Rynders (p. 483), only Translocation Down Syndrome is passed from parent to child, and in a very small percentage. The risk also depends on the sex of the career; mothers have a higher chance of passing the condition as compared to fathers. However, there are some risk factors that predispose people to Down syndrome. These include advanced maternal age, having a child who has Down syndrome, being careers of the genetic factors (IMDSA, para. 4).
Down syndrome, in some cases, can lead to health complications like heart problems or leukemia. Children should therefore be managed well and support from and to each member of the family is also important. There are many support groups available for such families and also schools that take care of the needs of such children.
Works Cited
International Mosaic Down Syndrome Association (IMDSA). What is Down Syndrome? 20, January 2013, Accessed 9, September 2014.
Laney, Dawn. Down Syndrome. Greenhaven Press, 2008. Print.
National Society of Genetic Counselors (NSGC). Down Syndrome. 13, Sept 2013, Accessed 9, September 2014.
Püschel, Siegfried & Rynders, John. Down Syndrome: Advances in Biomedicine and Behavioral Sciences. Ware Press, 1982. Print.
Tingey, Carole. Down syndrome: A Resource Handbook. Little Brown, 1988. Print.
