Autosomal Recessive Disease

Autosomal recessive diseases are Reference genetic diseases Opens New Window that are passed to a child through both parents' Reference chromosomes Opens New Window.

Each person inherits 23 chromosomes from each parent and so has 23 pairs of chromosomes. Each chromosome contains Reference genes Opens New Window. One or both of the chromosomes in a pair may contain a changed (mutated) gene that could cause a genetic disease. In an autosomal recessive disease, both chromosomes in a pair must have a changed gene for the person to have the disease. If only one chromosome has a changed gene, the person is a Reference carrier Opens New Window and does not have symptoms.

If both parents carry the gene, there is a:

• 25% chance in each pregnancy that their child will inherit the changed gene from each parent (two genes) and have the disease.
• 50% chance in each pregnancy that their child will receive one changed gene and be a carrier.
• 25% chance in each pregnancy that their child will not receive the changed gene and be neither a carrier nor have the disease.

If only one parent carries the gene, there is a 50% chance in each pregnancy that the child will:

• Receive the changed gene and be a carrier.
• Not receive the changed gene and be neither a carrier nor have the disease.

If neither parent carries the gene, the child will not have this type of disease.

See a diagram of the Reference chances of passing on an autosomal recessive disease Opens New Window Reference Opens New Window.

Autosomal recessive diseases include Reference Tay-Sachs disease Opens New Window, Reference cystic fibrosis Opens New Window, Reference sickle cell disease Opens New Window, autosomal recessive Reference polycystic kidney disease Opens New Window (ARPKD), and Reference phenylketonuria Opens New Window (PKU).

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This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.