Department of Dermatology, Jinling Hospital, Nanjing University, School of Medicine, Nanjing, 210002, China.
Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China.
BMC Med Genet. 2020 Mar 30;21(1):67. doi: 10.1186/s12881-020-00997-0.
Xeroderma pigmentosum (XP) is a rare autosomal recessive genodermatosis. There are eight complementation groups of XP (XP-A to G and a variant form). XP-E is one of the least common forms, and XP-E patients are generally not diagnosed until they are adults due to a later onset of skin alterations.
We report a case of a 28-year-old Chinese woman with freckle-like hyperpigmented macules in a sun-exposed area who is prone to develop basal cell carcinomas. A genetic study revealed a novel homozygous c.111_112del deletion in exon 1 of the DDB2 gene. Western blotting analysis revealed that the patient lacked the expression of the wild-type mature DDB2 protein. The proband was first diagnosed with XPE on the basis of clinical findings and genetic testing. Sun protection was recommended, and the patient did not develop any skin cancers during the one-year follow-up.
We identified a novel homozygous deletion in DDB2 gene in Chinese XP-E patients having unique clinical features.
着色性干皮病（XP）是一种罕见的常染色体隐性遗传皮肤病。XP 有八个互补组（XP-A 到 G 和一种变体形式）。XP-E 是最不常见的形式之一，由于皮肤改变的发病较晚，XP-E 患者通常要到成年后才能被诊断出来。
我们报告了一例 28 岁的中国女性，其在暴露于阳光下的区域有雀斑样色素沉着过度斑，易发生基底细胞癌。基因研究显示 DDB2 基因外显子 1 中存在 novel homozygous c.111_112del 缺失。Western blot 分析显示该患者缺乏野生型成熟 DDB2 蛋白的表达。该先证者首先根据临床发现和基因检测被诊断为 XPE。建议进行防晒，在一年的随访中，患者未发生任何皮肤癌。
我们在中国 XP-E 患者中发现了 DDB2 基因的 novel homozygous 缺失，这些患者具有独特的临床特征。
