Question

With respect to phenyl ketonuria identify which statement is not correct :-

• A. It is an error in metabolism
• B. Caused due to autosomal recessive trait
• C. It is an example of pleiotropy
• D. It is a case of aneuploidy.

Answer 1

The correct option is D It is a case of aneuploidy.

Phenylketonuria is a recessive autosomal disorder related to phenylalanine metabolism. This disorder is due to the absence of a liver enzyme phenylalanine hydroxylase. Due to the lack of this enzyme, phenylalanine follows another pathway and gets converted into phenyl pyruvic acid. This phenyl pyruvic acid upon accumulation in joints causes arthritis. If it hits the brain, it causes mental retardation known as phenyl pyruvic idiocy.

So, the correct option is ‘it is a case of aneuploidy’.