Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, China; Shanghai Institute for Pediatric Research, China.
Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, China; Shanghai Institute for Pediatric Research, China.
Gene. 2014 Mar 1;537(1):140-2. doi: 10.1016/j.gene.2013.12.018. Epub 2013 Dec 26.
Opitz G/BBB syndrome (OS) is a genetically heterogeneous disease. We report on an OS patient with a novel inherited mutation in MID1. Metaphase analysis showed a normal male karyotype. Array CGH revealed a maternally inherited duplication at Xp22.31 (6,467,203-7,992,261, hg18), the size was estimated to 1.5Mb. Sequence analysis of the MID1 coding region revealed a novel missense mutation in exon 8 (c.1561C>T/p. R521C) which resulted in an ammonia acid substitution (R521C) in the PRX domain of the MID1 protein. The mutation was inherited from unaffected grandmother and mildly affected mother. Prenatal diagnosis was performed for the third pregnancy after identification of the causative mutation in the family. The third fetus was found to be a female carrier. Postnatal follow-up at 2-month-old showed normal phenotype. In conclusion, we reported a familial OS patient with a novel mutation in exon 8 which provided another evidence for that mutation clustered in C-terminal domain of MID1. The newly identified mutation in our patient expands mutation spectrum in MID1 gene.
Opitz G/BBB 综合征（OS）是一种遗传异质性疾病。我们报告了一例 OS 患者，其 MID1 中存在新的遗传性突变。中期分析显示正常的男性核型。Array CGH 显示 Xp22.31（hg18 上的 6,467,203-7,992,261）处存在母系遗传的重复，大小估计为 1.5Mb。MID1 编码区的序列分析显示第 8 外显子中存在一个新的错义突变（c.1561C>T/p. R521C），导致 MID1 蛋白的 PRX 结构域中出现一个氨基酸取代（R521C）。该突变从无影响的祖母和轻度受影响的母亲那里遗传而来。在确定家族中的致病突变后，对第三次妊娠进行了产前诊断。第三个胎儿被发现是女性携带者。出生后 2 个月的随访显示正常表型。总之，我们报告了一例家族性 OS 患者，其第 8 外显子存在新突变，这为 MID1 中突变簇集在 C 末端提供了另一个证据。我们患者中新发现的突变扩展了 MID1 基因中的突变谱。
