Identification of a Novel Pathogenic XPC:c.2420+1G>C Variant in a Patient with Xeroderma Pigmentosum

This study reports a novel pathogenic variant, XPC:c.2420+1G>C, in an 8-year-old girl with Xeroderma Pigmentosum group C (XP-C), a condition marked by extreme UV sensitivity due to XPC gene mutations. The patient exhibited skin abnormalities, bilateral blepharoconjunctivitis, and severe dry eye syndrome. Genetic analysis revealed that this mutation causes a one-base-pair deletion at the splice donor site of exon 13, leading to a frameshift and premature stop codon in exon 14, impairing DNA repair. The study highlights the importance of regular monitoring for disease progression and precancerous lesions in affected individuals.