Biochemistry – MCQ 92 – Enzymes affected in Xeroderma pigmentosum

Xeroderma pigmentosum is produced as a result of a defect in :
A. DNA polymerase III
B. DNA polymerase I
C. DNA exonuclease
D. DNA ligase

Correct answer : B. DNA polymerase I or D. DNA ligase

Xeroderma pigmentosum is an autosomal recessive disease with defect in DNA repair. It is characterised by extreme sensitivity to sunlight. The enzymes affected in this condition are:
1. UV specific endonuclease (most common)
2. DNA polymerase I
3. DNA ligase