When a major TV network decided to air a show about a teen with Down syndrome (DS), a lot of people thought such a show would never be accepted by the viewing audience. But the American people soon began to look past Corky’s facial features and slightly unusual speech to the heart and personality inside. Life Goes
On was a hit, and it gave the audience a chance to look at their unfounded fear and prejudice toward the mentally retarded.
Down syndrome is one of many problems that can be identified at birth. A birth defect is an abnormality of structure, function, or metabolism that can result from inherited genetic traits, environmental influences, or both. Down syndrome, named for its discoverer, J. Langdon Down, was first recognized in 1866. Today, we know it is caused by an extra chromosome. The characteristics of Down syndrome include mental retardation; slanting eyes; a long, thick tongue; short hands and feet; and sometimes heart defects. The mental retardation ranges from mild to severe, with an IQ ranging from 30 to 70 (normal is 90 to 110). The incidence of Down syndrome is one in 600 births, but the odds increase with the age of the mother. A woman over 35, for example, has a five to 10 times greater risk of having a DS child than a woman under 35. Researchers have believed that this may be due to the aging of eggs in the ovary. Recent research, however, has indicated that there may be a connection between Alzheimer’s disease (a brain disorder found in older people) and Down syndrome. Families with a history of Alzheimer’s are three times as likely to have a child with Down syndrome as other families.
Down syndrome can be detected by amniocentesis in the second trimester of pregnancy, but, unfortunately, it cannot be cured. The life expectancy of a child with Down syndrome has increased as experts find ways to cope with the problems that accompany the disorder.
Another birth defect is spina bifida. One out of every 1,000 babies born in the United States has spina bifida, a malformation of the neural tube that develops into the brain and spinal cord during the first month of fetal development. In the most severe cases, the spinal cord and its covering push through an opening in the vertebral column, sometimes protruding into a sac on the outside of the lower back. This may result in partial paralysis, bladder problems, and an enlarged head, caused by an accumulation of fluid. Spina bifida is believed to be a combination of heredity, environment, and vitamin deficiencies. The disorder can be detected before birth through ultrasound and amniocentesis. Recently, a blood test that identifies certain neural tube proteins has been developed as a preliminary test.
After birth, many things can be done to help a child with spina bifida. Surgical repair of the spine and a shunt to relieve fluid buildup in the brain are common treatments. Some persons with spina bifida also experience mental retardation.
Most of us have had respiratory infections, coughs, and colds. But those with cystic fibrosis (CF) don’t know a time without lung congestion, wheezing, coughing, and a variety of other symptoms. This birth defect, caused by a recessive gene, affects one in 1,600 babies, mostly Caucasian, and kills about 500 each year. The abnormal gene suppresses a protein in the cell walls. This causes secretion of thick, sticky mucus that clogs the lungs and airways. It may even interfere with digestion. Persons with CF often have lung infections, as well as respiratory collapse, malnutrition, and sometimes intestinal blockages. Babies may not be diagnosed until an infection begins. (CF is identified through a test that measures the salt content of perspiration.)
CF treatment attempts to keep the airways clear of mucus using several methods. When the disease affects the digestive system, special enzymes and vitamins can help, along with a special diet. To date, there is no cure, and about half the victims die before age 20. Recent research, however, has identified the defective gene. This paves the way to the development of better treatment, and possibly a cure.
Because these birth defects can be identified before birth or shortly after, there’s a greater chance for developing better treatment and possible cures.
FAS– A Birth Defect That Can be Prevented
Fetal Alcohol syndrome (FAS) is an environmentally caused birth defect. It is caused by the mother-to-be drinking alcohol during pregnancy. The amount of alcohol it takes to cause this defect is not certain, so current recommendations are that pregnant women not drink alcohol at all.
FAS children have a variety of problems including growth deficiency, facial malformation, central nervous system dysfunction, and organ malformation. FAS children have a small head, flat midface, sunken nasal bridge, an elongated groove between the nose and upper lip, and heart defects. These children are slow to learn and never really catch up to their peers. They may have jittery and poorly coordinated movement and short attention spans. Many develop serious behavior problems.
Alcohol creates problems because it can cross the placenta and affect the fast-growing tissues by Killing cells or slowing growth. At birth, some FAS infants go through withdrawal-like symptoms including tremors and convulsions.
The good news about FAS is that it is preventable. Pregnant women are advised not to drink at all during pregnancy.