When abnormal cell division occurs in the 21st chromosome, this can commonly lead to Down Syndrome development. There are three different types of abnormalities in cell division that can occur, each resulting in extraneous genetic material, which leads to the characteristic features of the condition. The three different variations are Trisomy 21, Mosaic Down Syndrome and Translocation Down Syndrome. Each presents itself in a different way, but Trisomy 21 is the most common, affecting as many as 90 percent of all children with Down Syndrome.
There are a wide variety of serious complications that can occur in children and even adults who have the condition. Because there are so many serious complications linked to this disease, it is vitally essential that those with Down Syndrome be examined on a regular basis in order to keep track of these potential side effects. Some of the most common complications associated with Down Syndrome include: heart defects, infectious diseases like pneumonia, leukemia, dementia, obesity, sleep apnea, seizures, premature aging, poor vision, skeletal problems and gastrointestinal blockages.
The most common sign of Down Syndrome is the distinct facial appearance that children with the disease will have. Not every child with Down Syndrome will have the same facial features, but there are a number of common facial features that may occur. These include a short neck, small head, flattened features on the face, a protruding tongue, eyes that slant upwards and unusually shaped ears. Children who are born with the disease may also experience poor muscle tone, excessive flexibility, broad and short hands and relatively short fingers. All of these signs point to the development of Down Syndrome.
The development of the disease is most commonly discovered during pregnancy. A high risk of Down Syndrome can be diagnosed with screening tests before the baby is born. This may include an ultrasound, a nuchal translucency screening test and blood examinations. Other prenatal tests include amniocentesis, chorionic villius sampling and percutaneous umbilical blood sampling. Once the baby is born, the diagnosis can be confirmed by noting physical characteristics of the newborn as well as a chromosomal karyotype where the childs chromosomes are analyzed in search of extra chromosome #21.
Down Syndrome cannot be prevented, but early intervention for an infant or child with the disease can significantly improve the childs ability to thrive. A child with Down Syndrome will still meet his or her developmental milestones, but typically more slowly than a healthy child. Early intervention programs are designed to stimulate the child at an early age so that he or she can thrive and meet developmental milestones more readily. A child with Down Syndrome should have a team of caregivers including pediatric doctors and specialists as well as physical therapists and occupational therapists in order to make sure that he or she continues to develop healthily.