联合STR连锁分析和PCR-SSCP分析对新疆地区PKU基因诊断

Gene diagnosis of phenylketonuria in 4 families from Xinjiang.

联合采用PCR -STR和PCR -SSCP 2种基因诊断方法分析 5个PKU家系。除家系 4母亲为STR纯合型外 ,其余家系双亲皆为杂合子。对家系 1(维族 ) 1例风险胎儿 (妊娠 6周流产 )进行了产前基因诊断和 1例新生儿 (出生 1天 )进行了基因诊断 ,均为携带者 ,并经出生后证实。应用PCR -SSCP分析发现 ,家系 2 (回族 )患儿为Exon7突变纯合子 ,家系 4 (汉族 )患儿为Exon7和Exon11突变复合体 ,其Exon11突变位于第 399位点 (GTA→GTT) ,可能为一致病突变。实践证明上述 2种基因诊断方法联合使用可对 5个家系所有其他成员进行 10 0 %基因诊断和产前基因诊断 ,并可有效检出突变所在位置。

To evaluate a fittable PKU gene diagnos is and prenatal gene diagnosis in Xinjiang.Methods:Two gene diagnosis methods,polymerase chain reaction-short tandem repeats(PCR-STR) and PCR-single strand conformation polymorphism(PCR-SSCP)were used to analyze phenylalanine hydroxylase (PAH)gene of 5 familes affected with phenylketonuria(PKU).Results:With linkage analysis by STR,accurate gene diagnosis can be made in 4 familes,except in family 4 only 50% exclusive diagnosis can be made due to the mother is homozygous for STR.One prenatal gene diagnosis and one postnatal gene diagnosis on a new born were performed in family 1,a Uygur family,both of the fetus and new-born are heterzygotes.No mutation was detected in exons 4～7 and 10～12 in family 1 by PCR-SSCP,It was found that the proband in family 2(Hui) is homozygous for exon 7 mutation.the proband in family 4 is compound for mutation in exon 7 and codon 399(GTA-GTT)in exon 11.Conclusions: Accurate gene diagnosis can be achieved in these familes with the combined methods.