What genetic disorder is associated with the HEXA gene?

The genetic disorder associated with the HEXA gene is Tay-Sachs disease. Tay-Sachs is a fatal genetic disorder that results in the destruction of nerve cells in the brain and spinal cord. This condition is caused by a deficiency of the enzyme hexosaminidase A (Hex-A), which is encoded by the HEXA gene located on chromosome 15. When the HEXA gene is mutated, it leads to the accumulation of GM2 gangliosides, which are toxic to nerve cells and ultimately result in the progressive neurological deficits characteristic of Tay-Sachs disease.

Understanding the role of the HEXA gene and its association with Tay-Sachs is crucial, as this condition exemplifies how a single gene mutation can lead to significant clinical manifestations. The condition is inherited in an autosomal recessive pattern, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to be affected by the disorder. This highlights the importance of genetic counseling in assessing the risk for this and similar genetic disorders in affected families.