One Hereditary Disease in Humans, Called Xeroderma Pigmentosum (XP), Makes

question 43

Multiple Choice

One hereditary disease in humans, called xeroderma pigmentosum (XP) , makes homozygous individuals exceptionally susceptible to UV-induced mutation damage in the cells of exposed tissue, especially skin. Without extraordinary avoidance of sunlight exposure, patients soon succumb to numerous skin cancers.
-Given the damage caused by UV, 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.