Down Syndrome
In many cases, Down syndrome is not inherited. Rather, it occurs at random during the meeting of the egg and sperm cells. The condition begins in chromosome 21. Presently, Down syndrome affects every 1 in 800-1000 infants born around the world.
Down syndrome can be diagnosed during infancy through genetic testing. A blood or skin sample is collected to check for the presence of an extra chromosome, called trisomy 21. Trisomy 21 is when there is a trio of chromosome 21 instead of two. The extra chromosome disrupts normal brain development and causes the features characteristic of Down syndrome.
The common effects include learning and speech difficulties, mental retardation, flattened facial features, and hypotonia (poor muscle tone). These individuals also have an increased risk of digestive problems, hearing loss, heart defects, and usually have hypothyroidism. Early intervention programs can help with enhancing growth and learning capabilities of individuals with Down syndrome, enabling most to live and work independently.
