联合采用连锁分析和突变检测进行苯丙酮尿症的产前基因诊断

目的 为经典型苯丙酮尿症(phenylketonuria,PKU)家系提供产前基因诊断.方法 联合采用短串联重复片段(short tandem repeats,STR)多态连锁分析和聚合酶链反应技术扩增苯丙氨酸羟化酶基因突变热区外显子直接测序,对3个经典型PKU先证者及家系成员进行综合分析.结果 家系1的STR连锁分析不能提供遗传信息,家系2、家系3可提供100%信息.突变检测共发现3个先证者均为苯丙氨酸羟化酶基因复合杂合突变,共检测到5种突变:Y166X、R243Q、R413P、EX6-96A＞G和IVS11-1G＞C,其中IVS11-1G＞C为国际首次报道的新突变.综合连锁分析和突变检测结果,确定家系1和家系2胎儿为PKU患者,家系3胎儿正常.结论 联合连锁分析和苯丙氨酸羟化酶基因突变检测,可为PKU家系提供可靠的产前诊断服务.

Abstract：

Objective To explore the prenatal genetic diagnosis for classic phenylketonuria (PKU) families.Methods Probands and their family members from three classic PKU families were analyzed by combining linkage analysis through short tandem repeats (STR) polymorphism and PCR-sequencing for the exons within mutation hot spot of phenylalanine hydroxylase gene.Results Linkage analysis found uninformative for Family 1,while 100 % confirmative information was obtained from Family 2 and 3.Sequencing showed compound heterozygous mutations of phenylalanine hydroxylase gene for all of the three probands.Five mutations were detected,namely Y166X,R243Q,R413P,EX6-96A ＞ G and IVS11-1G＞ C,and IVS11-1G ＞ C was a novel identified muntation.Information from linkage analysis and mutation screening showed clearly that the fetus of Family 1 and 2 were affected,while normal for Family 3.Conclusions For those PKU families,reliable service of prenatal genetic diagnosis could be provided by combining linkage analysis with mutation screening of phenylalanine hydroxylase gene.

Prenatal genetic diagnosis for phenylketonuria families by combination of linkage analysis and mutation screening

Objective To explore the prenatal genetic diagnosis for classic phenylketonuria (PKU) families.Methods Probands and their family members from three classic PKU families were analyzed by combining linkage analysis through short tandem repeats (STR) polymorphism and PCR-sequencing for the exons within mutation hot spot of phenylalanine hydroxylase gene.Results Linkage analysis found uninformative for Family 1,while 100 % confirmative information was obtained from Family 2 and 3.Sequencing showed compound heterozygous mutations of phenylalanine hydroxylase gene for all of the three probands.Five mutations were detected,namely Y166X,R243Q,R413P,EX6-96A ＞ G and IVS11-1G＞ C,and IVS11-1G ＞ C was a novel identified muntation.Information from linkage analysis and mutation screening showed clearly that the fetus of Family 1 and 2 were affected,while normal for Family 3.Conclusions For those PKU families,reliable service of prenatal genetic diagnosis could be provided by combining linkage analysis with mutation screening of phenylalanine hydroxylase gene.