Which of the following is true about xeroderma pigmentosa?

Which of the following is true about
xeroderma pigmentosa?
a) Autosomal dominant
b) Good long term prognosis
c) Purine dimmers
d) DNA repair defect
Correct Answer - D
Ans. D. DNA repair defect
[Ref Rook’s 4thie p. 78.12]
Xeroderma pigmentosa
Molecular defect:
Exposure to UV rays damages DNA due to production of convalent
linkages between adjacent pyrimidines (pyrimidine dimmers).
Normally the damaged DNA is repaired by excision and repair.
In xeroderma pigmentosa the repair of UV damaged DNA is
defective.
It is an autosomal recessive disorder.