PAX6基因突变的鉴定与中国家系无虹膜症合并妊娠期糖尿病的产前诊断

目的：探讨1个中国无虹膜症合并妊娠期糖尿病家系的基因缺陷及产前诊断。

方法：收集1个患有无虹膜症合并妊娠期糖尿病的中国家系，从外周血中提取整个家系成员的基因组DNA，通过聚合酶链式反应结合直接测序法，分析人类配对盒基因(PAX6)的编码序列。妊娠18wk时对孕妇进行羊膜穿刺术，并根据突变筛查结果进行遗传学分析。

结果：无虹膜患者在PAX6的第5外显子中存在杂合缺失突变(c.113_129del GGCCGTGCGACATTTCC， p.Arg38ProfsTer12)，该患者同时合并妊娠期糖尿病，产前诊断结果提示胎儿具有相同的突变，易患先天性无虹膜症，经产后随访证实。

结论：在中国先天性无虹膜患者中发现了PAX6基因缺失突变，为人类PAX6等位基因变异数据库提供了更多的文献资料，为产前诊断提供了分析依据。

Mutation identification of PAX6 and prenatal diagnosis in a Chinese family with Aniridia and gestational diabetes

AIM:To explore the genetic defects and prenatal diagnosis of a Chinese family with aniridia and gestational diabetes.

METHODS: We recruited a Chinese family with aniridia and gestational diabetes. Genomic DNA of the whole family individuals was extracted from the peripheral blood leukocytes. Encoding regions of the paired box 6(PAX6)gene was screened by PCR direct sequencing. Amniocentesis was carried out on the affected female at 18wk of gestation, and subsequently, genetics analysis was performed based on the result of mutation screening.

RESULTS: In this study, the patients with aniridia and congenital cataract carried a heterozygous deletion mutation(c.113_129del GGCCGTGCGACATTTCC, p.Arg38ProfsTer12)in exon 5 of PAX6. One of the patients was affected with diabetes while this lady also had gestational diabetes. The result of prenatal diagnosis suggested the fetus carried the same mutation and will be affected with the aniridia, which was confirmed by postpartum follow-up.

CONCLUSION: It was suggested that a reported deletion mutation in the PAX6 was identified again in a Chinese family with aniridia and congenital cataract. It contributed to more literature information for the human PAX6 allelic variant database and provided an analysis basis for prenatal diagnosis.