Deficiency of enzyme hexosaminidase, subunit causes –
**Core Concept**
Hexosaminidase is a lysosomal enzyme responsible for breaking down gangliosides, a type of complex lipid found in the brain and nervous system. The deficiency of this enzyme leads to the accumulation of gangliosides, resulting in a severe neurological disorder.
**Why the Correct Answer is Right**
The correct answer is related to Tay-Sachs disease, a rare genetic disorder caused by the deficiency of the alpha subunit of hexosaminidase A. This enzyme deficiency results in the accumulation of GM2 ganglioside within neurons, leading to their degeneration and death. The clinical manifestations of Tay-Sachs disease include progressive weakness, muscle stiffness, and loss of motor skills, ultimately leading to death.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify the subunit of hexosaminidase involved. Hexosaminidase has multiple subunits, and a deficiency in a different subunit would lead to a different disease.
**Option B:** This option is incorrect because it refers to Fabry disease, which is caused by a deficiency of the enzyme alpha-Galactosidase A, not hexosaminidase.
**Option C:** This option is incorrect because it refers to Krabbe disease, which is caused by a deficiency of the enzyme galactocerebrosidase, not hexosaminidase.
**Clinical Pearl / High-Yield Fact**
Tay-Sachs disease is an autosomal recessive disorder, meaning that a person must inherit two copies of the mutated gene (one from each parent) to develop the disease. It is essential to remember that Tay-Sachs disease is a lysosomal storage disorder, and its symptoms can be managed with supportive care, but there is no cure for the disease.
**Correct Answer:** D.