Question

Menkes disease is associated with which enzyme deficiency.

• A. lysyl oxidase
• B. Methionine synthase
• C. Glutamyl aminopeptidase
• D. Lysyl hydroxylase

Answer 1

The Correct Option is A

Menkes disease is a rare, X-linked recessive disorder caused by a defect in copper metabolism, which leads to systemic copper deficiency. The key feature of this disease is the deficiency in activity of several copper-dependent enzymes, one of which is lysyl oxidase. Lysyl oxidase is crucial for the cross-linking of collagen and elastin fibers, vital components for connective tissue strength and elasticity.

In Menkes disease, the genetic mutation affects transport of copper, inhibiting its absorption and distribution, leading to a deficiency in this element. Since lysyl oxidase requires copper as a cofactor, its enzymatic activity is reduced, impairing the structural integrity of connective tissues. Clinical symptoms of Menkes disease include kinky hair, growth retardation, and neuronal degeneration.

Given the options:

• lysyl oxidase
• Methionine synthase
• Glutamyl aminopeptidase
• Lysyl hydroxylase

The enzyme deficiency associated with Menkes disease is lysyl oxidase. Other enzymes listed do not have a direct role in Menkes disease and are not primarily dependent on copper as a cofactor, distinguishing lysyl oxidase as the correct association.