Autosomal recessive is a type of inheritance pattern seen in humans for certain genetic disorders. It is caused by a mutation in a gene located on one of the autosomes, which are non-sex chromosomes (chromosomes other than X and Y). In this type of inheritance, both copies of the gene (one from each parent) must be mutated for the disorder to be present. If only one copy is mutated, the individual is considered a carrier of the disorder but does not show any symptoms.

Characteristics of Autosomal Recessive Inheritance:

• Requires two copies of the mutated gene for the disorder to be expressed
• Both parents must be carriers or affected by the disorder to pass it on to offspring
• Each child of carrier parents has a 25% chance of being affected by the disorder
• Approximately 1 in 4 individuals in a population are carriers for an autosomal recessive disorder
• Disorders inherited in an autosomal recessive manner often result from loss of function mutations in the gene

Examples of Autosomal Recessive Disorders:

• Cystic fibrosis
• Sickle cell anemia
• Tay-Sachs disease
• Phenylketonuria (PKU)

Testing and Treatment:

Genetic testing can be performed to identify carriers of autosomal recessive disorders, allowing individuals to make informed family planning decisions. Treatment of autosomal recessive disorders typically involves symptom management and supportive care, as there may not be a cure for the underlying genetic condition.