Schreiber W E, Fong F, Nassar B A, Jamani A
Division of Clinical Chemistry, Vancouver Hospital, British Columbia, Canada.
Hum Genet. 1995 Aug;96(2):161-6. doi: 10.1007/BF00207373.
We used heteroduplex analysis to screen for mutations in the porphobilinogen deaminase gene in 21 patients with acute intermittent porphyria (AIP). Unique banding patterns were investigated by direct sequencing of polymerase chain reaction products and, when indicated, sequencing of cloned DNA containing the exon of interest. Two frameshift mutations were found, a 2-bp deletion in exon 5 and a 1-bp insertion in exon 7. Both mutations generate a premature stop codon. Two point mutations, in exons 10 and 14, were also observed. The C-->T mutation in exon 10 codes for an Arg173 to Trp substitution, while a G-->A mutation in exon 14 changes Trp283 into a premature stop codon. This study extends the spectrum of mutations that cause AIP and demonstrates the utility of heteroduplex analysis as a screening technique.
我们采用异源双链分析技术，对21例急性间歇性卟啉病（AIP）患者的胆色素原脱氨酶基因进行突变筛查。通过对聚合酶链反应产物进行直接测序，以及在必要时对含有目标外显子的克隆DNA进行测序，研究独特的条带模式。发现了两个移码突变，一个是外显子5中的2个碱基缺失，另一个是外显子7中的1个碱基插入。这两个突变均产生过早的终止密码子。还观察到外显子10和14中的两个点突变。外显子10中的C→T突变导致Arg173被Trp替代，而外显子14中的G→A突变将Trp283变为过早的终止密码子。本研究扩展了导致AIP的突变谱，并证明了异源双链分析作为一种筛查技术的实用性。
