What is the inheritance pattern of Friedrich ataxia?

Friedreich ataxia is a hereditary degenerative disease that primarily affects the nervous system and the heart. The correct inheritance pattern for Friedrich ataxia is autosomal recessive. This means that for an individual to express symptoms of the disease, they must inherit two copies of the faulty gene—one from each parent.

In the case of Friedrich ataxia, the gene involved is known as FXN, which provides instructions for producing the frataxin protein. The absence or insufficient production of frataxin leads to the degeneration of nerve cells in the spinal cord and peripheral nerves, resulting in coordination issues and movement difficulties characteristic of the condition.

This inheritance pattern is significant because it implies that carriers of the gene defect (individuals who have one normal copy and one mutated copy) do not show symptoms of the disease. Understanding this pattern is critical in genetic counseling, where families can be informed about their risk of having affected children based on their own genetic makeup and family history.