Molecular genetic pathology is the laboratory study of genetic samples of cells, tissues, body fluids, and organs, associated with heredity. A genetic pathologist identifies the causes, processes, and risks of inherited diseases through microscopic study. Laboratory test results of genetic material help to diagnose, confirm, and monitor inherited diseases. The genetic pathologist can provide counseling to patients and their families, with information about their condition and the risk of a genetic disorder in the family.

Laboratory study of tissue and fluid samples can help to 1) diagnose inherited genetic abnormalities and tumor malignancies, 2) monitor genetic changes of patients who have undergone bone marrow transplants, 3) diagnose and monitor viral, fungal, and bacterial infections.

Doctor density varies by specialty and location. The United States has 75 practicing molecular genetic pathologists. Broken out by state, molecular genetic pathology doctor density in Arizona is 2, in Arkansas is 4, in California is 14, in Colorado is 2, in Connecticut is 5, in District of Columbia is 4, in Florida is 6, in Georgia is 5, in Illinois is 5, in Indiana is 2, in Iowa is 3, in Kentucky is 1, in Maine is 1, in Maryland is 6, in Massachusetts is 8, in Michigan is 3, in Minnesota is 6, in Missouri is 4, in Montana is 1, in New Jersey is 2, in New York is 20, in North Carolina is 12, in Ohio is 5, in Oklahoma is 2, in Oregon is 2, in Pennsylvania is 5, in Rhode Island is 1, in Tennessee is 1, in Texas is 14, in Utah is 5, in Vermont is 2, in Virginia is 2, in Washington is 1, in Wisconsin is 3, and in Wyoming is 1.