DNA Replication & Repair MCAT Practice Question
A patient presents with xeroderma pigmentosum, a rare genetic disorder characterized by extreme sensitivity to sunlight and high incidence of skin cancer. Genetic testing reveals defects in nucleotide excision repair (NER) pathway components. Which type of DNA damage caused by UV radiation is primarily repaired through the nucleotide excision repair pathway?
Answer choices
- DThymine dimers and 6-4 photoproductsCorrect answer
- ADepurination and depyrimidination
- BSpontaneous cytosine deamination
- CSingle-strand breaks from ionizing radiation
- EInterstrand crosslinks from mitomycin C
- FOxidative guanine damage and 8-oxoguanine lesions
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