Pyrimidine dimers are formed due to
Correct Answer: UV rays
Description: Pyrimidine dimers are molecular lesions formed from thymine or cytosine bases in DNA photochemical reactions. Ultraviolet light induces the formation of covalent linkages by reactions localized on the C=C double bonds. In dsRNA (double-stranded RNA), uracil dimers may also accumulate as a result of UV radiation. Two common UV products are cyclobutane pyrimidine dimers (CPDs, including thymine dimers) and 6,4 photoproducts. These premutagenic lesions alter the structure of DNA and consequently inhibit polymerases and arrest replication. Dimers may be repaired by photoreactivation or nucleotide excision repair, but unrepaired dimers are mutagenic. Pyrimidine dimers are the primary cause of melanomas in humans Ref-Harpers illustrated biochemistry 30/e p279
Category:
Biochemistry
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now