Autosomal dominant

Autosomal Dominant is a term used in genetics to describe a mode of genetic inheritance where an affected individual has one copy of a mutant gene and one normal gene on a pair of autosomal chromosomes.

Overview

In an autosomal dominant condition, the mutant gene is a dominant gene located on one of the autosomes (chromosomes 1 through 22). Autosomal dominant conditions are traits or disorders that are present when only one copy of the mutation is inherited on a non-sex chromosome. In these types of conditions, the individual has one normal copy and one mutant copy of the gene. The chance of passing the abnormal gene from an affected parent to an offspring is 50% for each pregnancy regardless of the sex of the resulting child.

Autosomal Dominant Disorders

There are numerous disorders which follow the autosomal dominant inheritance pattern. Some of these include Huntington's disease, Marfan syndrome, neurofibromatosis type 1, and polycystic kidney disease.

Huntington's Disease

Huntington's disease is a neurodegenerative genetic disorder that affects muscle coordination and leads to cognitive decline and psychiatric problems. It typically becomes noticeable in mid-adult life, with symptoms often beginning between 30 and 50 years of age.

Marfan Syndrome

Marfan syndrome is a genetic disorder of the connective tissue. People with Marfan tend to be unusually tall, with long limbs and long, thin fingers. The most serious complications involve the heart and aorta, with an increased risk of mitral valve prolapse and aortic aneurysm.

Neurofibromatosis Type 1

Neurofibromatosis type 1 is a complex multi-system human disorder caused by the mutation of a gene on chromosome 17 that is responsible for production of a protein called neurofibromin which is needed for normal function in many human cell types.

Polycystic Kidney Disease

Polycystic kidney disease (PKD) is a genetic disorder characterized by the growth of numerous cysts in the kidneys. PKD cysts can slowly replace much of the kidneys, reducing kidney function and leading to kidney failure.

See Also

• Autosomal recessive
• X-linked dominant
• X-linked recessive
• Y-linked