2019 年第 5 期 第 14 卷

全外显子测序技术对原发性双侧肾上腺大结节样增生患者进行家系筛查的价值

Whole exon sequencing of gene mutation in a family of primary bilateral macronodular adrenal hyperplasia

作者：匡泽民王瑛唐欣颖奉淑君江龙王永兴

英文作者：

单位：100029首都医科大学附属北京安贞医院高血压科（匡泽民），泌尿外科（王永兴）；471000河南省洛阳市，河南科技大学第二附属医院心内科（王瑛）；423000南华大学附属郴州市第一人民医院心内科（唐欣颖、奉淑君）；330006南昌大学第二附属医院心血管内科（江龙）

英文单位：

关键词：原发性双侧肾上腺大结节样增生；全外显子测序；ARMC5基因；生物信息学分析

英文关键词：

• 摘要：

• 【摘要】目的    探讨全外显子测序技术对原发性双侧肾上腺大结节样增生（PBMAH）患者家系成员进行致病基因突变筛查的价值。方法    选择2017年就诊于首都医科大学附属北京安贞医院高血压科门诊的PBMAH患者1例（先证者），先证者家系由4代18名成员组成，其中先证者祖父母（Ⅰ-1和Ⅰ-2）已逝，共纳入16名研究对象，患病成员共3名，分别为先证者、先证者之父和先证者之弟。本研究选择对3名患病成员及先证者之子共4名家系成员进行全外显子组测序和生物信息学分析，利用千人基因组、dbSNP、Clinvar、Cosmic等数据库对测序结果进行分析，确定致病突变位点，并对纳入成员进行Sanger测序验证。结果    该家系所有患者均为男性，家系内患者肾上腺CT均提示双侧肾上腺增生，结节直径均>10 mm，但临床表型异质性较大。全外显子测序结合生物信息学分析，最终得到包括791个非同义突变在内的共3 936个突变位点，这些突变位点没有任何已知的PBMAH及库欣综合征的基因，其中的208个位点对蛋白功能有影响，千人基因组频率小于0.05的共60个位点，去掉ClinVar数据库中评级为良性的，最后候选突变位点56个。Sanger测序结果表明,只有1个位于ARMC5基因上的点突变c.1085G>A呈现出基因型与疾病表型分离，考虑此突变位点可能为该家系致病突变位点。结论    为了避免患者长期处于皮质醇增多症状态而影响预后，早期识别PBMAH尤为重要，对PBMAH患者进行家系筛查有助于疾病早期诊断和干预。

• 【Abstract】Objective    To investigate the value of whole exon sequencing of pathogenic gene mutation in a family of primary bilateral macronodular adrenal hyperplasia(PBMAH). Methods    One patient with PBMAH(the proband) who visited Beijing Anzhen Hospital, Capital Medical University in 2017 was selected. The family of the proband consisted of 18 members from 4 generations; the grandparents(Ⅰ-1 and Ⅰ-2) of the proband had passed away; 16 family members were finally included. There were 3 sick members, the proband, the father and the younger brother. Whole exon sequencing was performed in the 3 sick members and the son of the proband; bioinformatics results were analyzed according to thousands of human genomes, dbSNP, Clinvar and Cosmic database to find the mutation site. The mutation site was verified by Sanger sequencing in all family members. Results    All sick members in the family were male; adrenal CT of them showed bilateral adrenal hyperplasia with nodular diameter>10 mm, but clinical phenotype showed great heterogeneity. Whole exon sequencing combined with bioinformatics analysis showed a total of 3 936 mutation sites including 791 non-synonymous mutations; these mutation sites did not include any known genes of PBMAH or Cushing syndrome; 208 mutation sites had affects on protein function; genome frequency of 60 mutation sites was less than 0.05; benign mutations in ClinVar database were removed; finally 56 candidate mutation sites were postulated. Sanger sequencing indicated that only 1 point mutation c.1085G>A located on ARMC5 gene showed a segregation between genotype and phenotype; this mutation was considered as the possible pathogenic mutation site of the family. Conclusions    In order to avoid long-term adverse response caused by hypercortisolism, early identification of PBMAH is particularly important. Whole exome sequencing in the family of PBMAH patients is helpful for early diagnosis and intervention.