Question

Krabbe's disease is caused by which enzyme deficiency?

• A. Deficiency of beta-galactosylceramidase
• B. Deficiency of aryl sulphatase
• C. Alpha galactosidase
• D. Acid lipase

Hint:

Globoid cell leukodystrophy and the GALC gene.

Answer 1

The Correct Option is A

Step 1: Krabbe disease, also called globoid cell leukodystrophy, is an autosomal recessive lysosomal storage disorder. Step 2: It results from mutations in the GALC gene on chromosome 14 (14q31), which cause deficiency of the enzyme galactosylceramidase (beta-galactocerebrosidase). Step 3: Loss of this enzyme leads to accumulation of psychosine (galactosylsphingosine), which is toxic to oligodendrocytes and causes severe demyelination with characteristic globoid cells. Step 4: Aryl sulphatase A deficiency causes metachromatic leukodystrophy, alpha galactosidase A deficiency causes Fabry disease, and acid lipase deficiency causes Wolman disease - all are wrong. Hence beta-galactosylceramidase deficiency is correct.