Normal chromosomes Q: Do genetic factors play a role in causing birth defects?
Yes, in some but not all cases. Changes in the genes can cause certain birth defects in infants. Genes tell each cell in the body how to combine with other cells to form parts of the body. For example, genes tell certain cells to make the heart, the kidneys, or the brain, and they tell other cells to make our physical features, like green eyes or brown hair. Genes also tell the cells how to work in the body. Genes give instructions for cells in our heart to beat, our stomach to digest food, our muscles to push and pull, and our brain to think. Genes combine with many other genes to make chromosomes. Changes in single genes, groups of genes, or entire chromosomes can sometimes cause birth defects. These genetic changes might happen only in the infant, or they might pass down from one or both parents. Sometimes, there are other relatives in the family with the same birth defect, but not always. Factors other than genetics can also increase the chance of having a baby with a birth defect.
