Given the damage caused by UV radiation, the kind of gene affected in those with XP is one whose product is involved with ________.
A) mending of double-strand breaks in the DNA backbone
B) breakage of cross-strand covalent bonds
C) the ability to excise single-strand damage and replace it
D) the removal of double-strand damaged areas
E) causing affected skin cells to undergo apoptosis

Question

Quizplus · Accepted Answer

XP (xeroderma pigmentosum) is a rare genetic disorder in which individuals are extremely sensitive to UV radiation due to a defect in their nucleotide excision repair (NER) mechanism. The NER pathway involves the excision of a single-stranded damaged area of DNA and its replacement with a newly synthesized strand. Therefore, the gene affected in those with XP is involved in the ability to excise single-strand damage and replace it. Choices A, B, D, and E are not directly related to the NER mechanism.

Given the Damage Caused by UV Radiation, the Kind of Gene