METHODS: A couple who had presented at the Affiliated Hospital of Putian College on March 3, 2021 was selected as the study subject. Following elective abortion, fetal tissue and peripheral blood samples were respectively obtained from the abortus and the couple, and were subjected to whole exome sequencing. Candidate variants were verified by Sanger sequencing.
RESULTS: The fetus was found to harbor compound heterozygous variants of the B3GALNT2 gene, namely c.261-2A>G and c.536T>C (p.Leu179Pro), which were inherited from its father and mother, respectively.According to the guidelines of American College of Medical Genetics and Genomics, both variants were classified as pathogenic (PVS1+PM2_Supporting; PM3+PM2_Supporting+PP3+PP4).
CONCLUSIONS: The compound heterozygous variants of the B3GALNT2 gene probably underlay the α-dystroglycanopathy in this fetus. Above results have provided a basis for genetic counseling of this pedigree.
方法:选取2021年3月3日在莆田学院附属医院就诊的一对夫妇作为研究对象。选择性流产后,分别从流产和夫妇中获得胎儿组织和外周血样本,并进行了全外显子组测序。通过Sanger测序验证候选变体。
结果:发现胎儿带有B3GALNT2基因的复合杂合变体,即c.261-2A>G和c.536T>C(p。Leu179Pro),从它的父亲和母亲那里继承下来,分别。根据美国医学遗传学和基因组学学院的指导方针,两种变体均被分类为致病性的(PVS1+PM2_支持;PM3+PM2_支持+PP3+PP4)。
结论:B3GALNT2基因的复合杂合变体可能是该胎儿的α-营养不良病的基础。以上结果为该家系的遗传咨询提供了依据。