多态性及基因测序分析方法研究苯丙酮尿症患者的基因突变

Polymorphism and Sequencing Analysis of Mutations in Patients with Phenylketonuria

应用聚合酶链反应-单链构象多态性分析及基因测序的方法,分析35例苯丙酮尿症患者PAH基因第6和7外显子以及其两侧部分内含子序列,进行了突变的筛查和确定。研究吉林地区苯丙酮尿症人群中苯丙氨酸羟化酶(Phenylalanine hydroxylase,PAH)基因突变特征。结果显示:(1)在70个PAH等位基因中共检测出9种不同突变基因,总检出率为44.2%。吉林地区常见的突变是R243Q和EX6-96A>G,其它较常见突变有IVS7+2T>A,R241C,L242F,G247R,G247V,R261X和R176X。(2)检测出两种多态性位点Q232Q和V245V,推测PAH基因cDNA序列存在人种差异和地域差异。明确了吉林地区PAH在第6和第7外显子基因及其两侧部分内含子突变类型与中国其它地区相似,高频率突变位点基因突变比例几乎一致,而其它突变位点的基因突变比例存在明显差异。

The mutations in exons 6 and 7 and the flanking intronic sequence of phenylalanine hydro-xylase（PAH） gene were detected by PCR/single strand conformation polymorphism（SSCP） analysis and direct DNA sequencing in 35 PKU patients.The characteristics of the exon 6 and exon 7 of PAH gene mutation in patients with phenylketonuria（PKU） in Jilin were also investigated and discussed.The results suggested that：（1） Nine different mutations were identified in 31/70 alleles（44.2%）.The most prevalent mutations were R243Q（25.7%） and EX6-96AG（5.7%）,followed by IVS7＋2TA（2.9%）,R241C（2.9%）,L242F（1.4%）,G247R（1.4%）,G247V（1.4%）,R261X（1.4%） and R176X（1.4%）.（2） Two polymorphism sites Q232Q（94.3%） and V245V（67.1%） were detected,which suggest that the ethnic diversity and area diversity exist in PAH cDNA sequence.The mutations of the PAH gene in Jilin were similar as that in other areas of China.There is identical with each high frequency of mutation and obvious difference with each other low frequency of mutation.