Which disorder is associated with convulsions, cataract and mental retardation?
**Core Concept**
The question is testing the association between a congenital disorder and its characteristic clinical features, including convulsions, cataract, and mental retardation. This is a classic example of a genetic disorder affecting multiple systems.
**Why the Correct Answer is Right**
The correct answer is associated with a congenital disorder caused by a mutation in the _GLC3A_ gene, which encodes the galactose-3-phosphate dehydrogenase enzyme. This enzyme plays a crucial role in the breakdown of galactose to glucose in the liver. When this enzyme is deficient, galactose-3-phosphate accumulates, leading to a range of clinical manifestations, including cataract, convulsions, and mental retardation. The disorder is known as Galactosemia.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not match the clinical features of the disorder being tested.
* **Option B:** This option is incorrect because it is associated with a different set of clinical features, including hypoglycemia, vomiting, and hepatomegaly.
* **Option C:** This option is incorrect because it is associated with a different congenital disorder, characterized by a failure of the lens to form properly in the eye.
**Clinical Pearl / High-Yield Fact**
Galactosemia is a classic example of a genetic disorder with a wide range of clinical manifestations, including cataract, convulsions, and mental retardation. It highlights the importance of early diagnosis and treatment to prevent long-term complications.
**Correct Answer:** C. Galactosemia.