Pedigree Used to show how a particular trait is passed from one generation to the next in a family

Allelic Disorders - genetic disorders are USUALLY recessive

Albinism Many forms, many genes code for it Lack of pigment in skin, hair, and eyes. Approx. 1 in 17,000 people Health Impacts 1.Eye problems 2.Severe sensitivity to sunburn.

Cystic Fibrosis Gene mutation on chromosome 7 Health: build up of mucus in the lungs, pneumonia One of the first disorders to be actively studied for gene therapy.

Sickle Cell Anemia Codominant disorder found in African Americans. Red blood cells are mishapen. Characterized by extreme pain in legs and arms because the cells get stuck in capillaries.

Tay-Sachs Fatal genetic disorder from a buildup of fatty substances in tissues and nerve cells in brain. Infants develop normally then deteriorate to become blind, deaf, unable to swallow leading to muscle atrophy and paralysis. Persons with Tay-Sachs also have "cherry-red" spots in their eyes. Both parents must carry the mutated gene in order to have an affected child.

Huntington’s Disease Results in a loss of muscle control and mental function. The symptoms usually do not appear until after 30 years old. Approximately 1 in 10,000 births Gene on chromosome 4

Huntington’s Disease

Color Blindness Recessive gene located on the X chromosome. Sex-Linked disorder Cannot distinguish red/green Does color blindness affect more men or women? MEN Why? Men only have one X chromosome, thus only one copy of the color blind gene.

Hemophilia A disorder in which a person’s blood does not clot properly. Gene found on X chromosome. 1 in 10,000 males born are afflicted.

Pedigree Chart and Symbols