目的 明确2个呈常染色体显性遗传的无虹膜症家系的临床特征,并找出导致该病的基因突变。方法 2个家系无虹膜症患者接受遗传咨询及眼科检查,并采用候选基因法分别对2个家系成员的人类配对盒基因6（human paired box gene 6,PAX6）进行突变筛查,对未检出突变的家系进成员行外显子捕获及全外显子组测序。结果 家系1患者完全符合无虹膜症的临床特征,家系2患者还出现上睑下垂的表型。突变筛查发现,家系1的PAX6基因存在一个已知的基因突变c.718C>T(p.Arg240*),但家系2未筛查到任何已知的基因突变。结论 家系1中发现一个PAX6基因突变(p.Arg240*),但在家系2中尚未筛查到致病基因,提示无虹膜症尚存在新的遗传异质性。
Objective: To study the clinical features of two pedigrees of families with autosomal dominant aniridia, and to identify the pathogenic genes of the 2 families. Methods: All affected members underwent interrogation and ophthalmological examinations. Screening for PAX6 gene mutations was carried out in the 2 families. Family 2 in which no mutation was detected was also detected by exon capture and whole exome sequencing. Results: The patients of Family 1 pedigrees were completely consistent with the clinical features of aniridia, and the patients of Family 2 also had furthermore the phenotype of ptosis. Mutation screening showed that there was a known PAX6 gene mutation c.718C>T (p.Arg240*) in Family 1, but no mutation of PAX6 gene and other known genes were detected in Family 2. Conclusions: A PAX6 gene mutation (p.Arg240*) is detected in pedigrees of Family 1, but no disease-causing gene is yet detected in pedigrees of Family 2, denoting there is a novel genetic heterogeneity in aniridia.
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