Trio-based de novo mutation analysis by whole exome sequencing in congenital microtia
10.3760/cma.j.cn114453-20200519-00302
- VernacularTitle:应用全外显子组测序技术进行小耳畸形核心家系新生突变分析
- Author:
Nuo SI
1
;
Bo PAN
;
Qinghua YANG
;
Yanyong ZHAO
;
Ye ZHANG
;
Haiyue JIANG
Author Information
1. 中国医学科学院北京协和医学院整形外科医院研究中心 100144
- Keywords:
Congenital microtia;
Inheritance patterns;
Mutation
- From:
Chinese Journal of Plastic Surgery
2021;37(2):205-212
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the role of de novo mutations (DNMs) in Chinese patients with non-syndromic congenital microtia by using whole exome sequencing in patient-parent trios and to detect the pathogenic DNMs, if there are any. Methods:Twenty-four Chinese trio families with congenital microtia were recruited from March 2017 to July 2018 at the Plastic Surgery Hospital of Chinese Academy of Medical Sciences. The patients, aged from 6 to 10 years old, 15 males and 9 females, had unilateral microtia, including 15 on the left and 9 on the right. After informed consent, peripheral blood was collected from patients and their unaffected parents.Whole exome sequencing was performed on all patients and their parents. DNMs in the coding region and canonical splicing sites were detected, and the number of DNMs in each patient was obtained. Each DNM was classified according to the ACMG standards and guidelines for the interpretation of sequence variants. In-silico prediction was performed using different algorithms and databases considering both variant-and gene-level implications. ExAc database, VarCards, Human Splicing Finder 3.1 software were used to predict each variant’s pathogenicity, including loss of function variant, missense variant and nonsynonymous variant. Mouse genome information database was used to detect the expression of the homologous gene, and David 6.8 bioinformatics database was used for pathway enrichment analysis of candidate genes. The Online Mendelian Inheritance in Man database was used to query the correspondence between candidate genes and human diseases.Results:Twenty-three DNMs were detected in 24 microtia trios. In each patient, there was 0-3 DNMs with no significant difference in population. Twelve missense variants, eight synonymous variants, one nonsense, one start codon variant, and one inframe indel were detected. Among them, a nonsense LRP12 mutation was classified as pathogenic according to ACMG guidelines. However, none of the variants were considered disease-causing according to in-silico predictions.Conclusions:Increased number or mutational burden of DMNs are not observed in Chinese patients with microtia. DMNs is not the primary cause of microtia, although rare DNMs in responsible genes could occasionally lead to cases.
