extra copy (complete or partial) of chromosome 21 (see Figurebelow)
developmental delays, distinctive facial appearance, and other abnormalities (see Figure below)
one X chromosome but no other sex chromosome (XO)
female with short height and infertility (inability to reproduce)
Triple X syndrome
three X chromosomes (XXX)
female with mild developmental delays and menstrual irregularities
one Y chromosome and two or more X chromosomes (XXY, XXXY)
Diagnosing Genetic Disorders
Professionals known as genetic counselors can help understand the risks if a children is being affected. If someone has a genetic disorder, they may be advised to have prenatal (“before birth”) testing to see if the fetus has any genetic abnormalities. One method of prenatal testing is amniocentesis. In this procedure, a few fetal cells are extracted from the fluid surrounding the fetus, and the fetal chromosomes are examined.
Treating Genetic Disorders
The symptoms of genetic disorders can sometimes be treated, but cures for genetic disorders are still in the early stages of development. One potential cure that has already been used with some success is gene therapy. This involves inserting normal genes into cells with mutant genes.