A 2-year-old child presents with acute psychomotor retardation, vision and hearing impairment, sharp enlargement of the liver and spleen. The child is diagnosed with hereditary Niemann-Pick disease. What genetic defect is the cause of this disease?

Answer options

1. Glucose 6-phosphatase deficiency
2. Amylo-1,6-glucosidase deficiency
3. Xanthine oxidase deficiency
4. Sphingomyelinase deficiency
5. Acid lipase deficiency

Explanation

A 2-year-old child presents with acute psychomotor retardation, vision and hearing impairment, sharp enlargement of the liver and spleen. The child is diagnosed with hereditary Niemann-Pick disease. What genetic defect is the cause of this disease?