Xeroderma pigmentosum, an autosomal recessive disorder, is caused due to defects in
Show Hint
- Nucleotide Excision Repair Pathway
- Base Excision Repair Pathway
- Double Strand Break Repair Pathway
- Homologous Recombination Repair Pathway
The Correct Option is A
Solution and Explanation
Step 1: Understand DNA damage.
UV radiation causes:
• Formation of thymine dimers
• Distortion of DNA structure
Step 2: Identify repair mechanism.
These lesions are normally repaired by: \[ Nucleotide Excision Repair (NER) \]
Step 3: Cause of disease.
In XP:
• NER pathway is defective
• DNA damage accumulates
• Leads to skin abnormalities and cancer risk
Step 4: Final conclusion.
Thus, the disorder is due to defect in: \[ Nucleotide Excision Repair Pathway \]
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