Slide show: How genetic disorders are inherited
Autosomal dominant inheritance pattern
Previous Next 3 of 6 Autosomal dominant inheritance pattern

In an autosomal dominant disorder, the abnormal (mutated) gene is located on one of the first 22 pairs of chromosomes (autosomes). You need only one copy of the abnormal gene to be affected by this type of disorder.

A person with an autosomal dominant disorder — in this case, the father — has a 50% chance of passing on the abnormal gene (and having an affected child) and a 50% chance of passing on the normal copy of the gene (and having an unaffected child) with every pregnancy.

Huntington's disease and Marfan syndrome are two examples of autosomal dominant disorders. Mutations to BRCA1 and BRCA2 genes — which have been associated with breast cancer — also are transmitted in this pattern.

Feb. 15, 2020