Abstract: Objective: To identify the pathogenic gene of a family with cutaneous amyloidosis with abnormal pigmentation (ACD). Methods: Peripheral blood DNA of the proband and her niece was extracted for high-throughput whole exome sequencing, and gene mutations were verified by Sanger sequencing. Results: Both the proband and her niece had homozygous mutation c.565C＞T in exon 5 and heterozygous mutation c.70+7A＞G in intron 1 of the GPNMB gene. Pathogenicity analysis was performed according to the variant interpretation guidelines issued by the American College of Medical Genetics and Genomics (ACMG). The homozygous mutation c.565C＞T was determined to be a pathogenic variant, while the clinical significance of the heterozygous mutation c.70+7A＞G was unclear. Conclusions: The c.565C＞T mutation in the GPNMB gene of this family may be related to the onset of ACD in this family.

Key words: cutaneous amyloidosis, dyschromia, GPNMB gene, mutation