Biochem C785 Readiness Exam

The LEP gene codes for an anorexigenic hormone. Interestingly, breastfeeding has been shown to alter methylation of the promoter of this gene, leading to increased LEP expression. What is likely happening in response to breastfeeding? - Breastfeeding decreases the methylation of the promoter of the LEP gene, increasing the spacing between nucleosomes. A patient with xeroderma pigmentosum is prone to developing multiple skin cancers starting in childhood. This occurs because of a mutation in a gene that codes for enzymes that help repair DNA damage through the nucleotide excision repair (NER) pathways. How does NER differ from other repair mechanisms? In NER: - The error in one strand of DNA is removed as well as several nucleotides on either side of the error. The gap that was removed is filled in by DNA polymerase