What is a genetic disorder, and how does a genetic disorder cause health and learning problems?
A genetic disorder is one that involves a difference in a chromosome or a single gene. Chromosomes are small structures found in every cell in the body. In human beings, each cell has 23 pairs of chromosomes. Each pair consists of one chromosome from the mother, carried in the ovum or egg, and one chromosome from the father, carried in the sperm that fertilized the egg. The chromosomes carry even smaller structures called genes. Genes contain the information that determines all of an individual’s characteristics — everything from height and eye color to predisposition to chronic illness. Occasionally, a baby is conceived with extra or missing chromosomal and genetic material. Since the chromosomes and the genes they contain orchestrate the body’s growth and development, a range of physical and behavioral problems may result. In the case of a chromosome 22q11.2 deletion, genetic material is missing (or deleted) from chromosome pair number 22. The “q” in the name of the disorder refers t