Week 5: DNA Synthesis

Question 1

How does xerodoma pigmentosum arise, and what are its hallmarks?

Answer 1

Hypersensitivity of the skin, high incidence of skin cancer

Xeroderma pigmentosum (XM) is characterized by a fault in DNA repair mechanisms. Most of the genes related to XP that are nonfunctional are part of the nucleotide excision repair (NER) pathway.

Question 2

How does Cockayne’s syndrome arise, and what are it’s hallmarks?

Answer 2

Cockayne syndrome is a rare disease that causes short stature, progeria, photosensitivity, microencephaly, and premature death

It arises from mutations in the ERCC6 gene (CSB) and the ERCC8 Gene (CSA), which provide instructions for repairing damaged DNA. As errors build up in these individuals, cells malfunction and eventually die.