Disorder shown in the Illustration is related to:
Ans. C. Nucleotide Excision RepairDisorder shown: Xeroderma pigmentosuma. Xeroderma pigmentosum (XP) is a rare autosomal recessive genetic disorder of DNA repair in which the ability to repair damage caused by ultraviolet (UV) light is deficient.b. In extreme cases, all exposure to sunlight must be forbidden, no matter how small; as such, individuals with the disease are often colloquially referred to as "Moon child".c. Multiple basal cell carcinomas (basaliomas) and other skin malignancies frequently occur at a young age in those with XP; metastatic malignant melanoma and squamous cell carcinoma are the two most common causes of death in XP victims.d. This disease is present in both genders and in all races, with an incidence of 1:250,000 in the United States. XP is roughly six times more common in Japanese people than in other groups.e. Normally, damage to DNA in epidermal cells occurs during exposure to UV light. The absorption of the high-energy light leads to the formation of pyrimidine dimers, namely cyclo butane-pyrimidine dimers and pyrimidine-6-4- pyrimidone photoproducts.f. In a healthy, normal human being, the damage is first excised by endonucleases. DNA polymerase then repairs the missing sequence, and ligase "seals" the transaction. This process is known as nucleotide excision repair.
Mismatch repair
Base excision repair
Nucleotide excision repair
SOS repair
Molecular Genetics