Xeroderma Pigmentosum, Group C (XPC)
Xeroderma pigmentosum, group C (XP-C) is an autosomal recessive disorder caused by pathogenic variants in the gene XPC. This disorder is characterized by increased sensitivity to sunlight due to defects in DNA repair. Individuals present with skin lesions and freckling generally in sun-exposed areas as well as dry skin and changes in skin coloring. Individuals may also experience ocular symptoms, specifically eye irritation, corneal clouding, and impaired vision. Unlike other types of XP, individuals with XP group C typically do not have neurological symptoms. Individuals with this disorder have a significantly increased risk of developing skin cancer. No clear genotype-phenotype correlation has been established.
For information about carrier frequency and residual risk, please see the residual risk table.