Question

What occurs to cause Tay-Sachs disease?

1) An extra chromosome
2) A defective gene on chromosome 15; when the body lacks hexosaminidase
3) Fetal Alcohol Syndrome
4) A defect in the CFTR gene, which makes a protein that controls the movement of salt and water in and out of the body's cells.

Answer 1

Tay-Sachs disease is a genetic disorder caused by a defective gene on chromosome 15, leading to a lack of the enzyme hexosaminidase A. It is an autosomal recessive disorder, so a child must inherit one copy of the defective gene from each parent to be affected.

Step-by-step explanation:

Causes of Tay-Sachs Disease:

Tay-Sachs disease is caused by a defective gene on chromosome 15. This defect leads to a shortage of an enzyme called hexosaminidase A (Hex-A), which is necessary for the breakdown of certain fatty substances in the brain and nerve cells. When these substances aren't properly degraded, they accumulate, leading to the destruction of neurons and severe neurological damage. Tay-Sachs is an autosomal recessive disorder, which means that a child must inherit one defective gene from each parent to be affected. Carriers of the Tay-Sachs gene, having only one copy of the defective gene, do not show symptoms of the disease. When two carriers have a child, there is a 25% chance that the child will inherit two defective genes and develop Tay-Sachs disease.