Odawara M, Matsunuma A, Yamashita K
Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan.
Hum Genet. 1997 Aug;100(2):163-6. doi: 10.1007/s004390050484.
A DD genotype of the angiotensin I-converting enzyme gene has been implicated in various diseases. However, genotype frequencies differ between previous reports, and data on the association of DD genotype with disease are sometimes conflicting. Although elimination of mistyping is of crucial importance, assessment of the accuracy of currently adopted typing methods has rarely been performed. Mistyping of the DD genotype is reported to occur by a conventional method with insertion/ deletion (I/D) flanking primers using polymerase chain reaction (PCR). We investigated whether currently adopted genotyping methods by PCR are reliable or not. We genotyped 248 patients by conventional PCR methods with I/D flanking primers with or without dimethyl sulfoxide (DMSO), and confirmed the DD genotype with insertion-specific primers with or without DMSO. Mistyping occurred frequently, not only in both methods without DMSO but also in a modified method with I/D flanking primers with inclusion of DMSO. Typing by these methods proved to lead to erroneous results more frequently than had been previously thought. To reduce mistyping frequency, initial PCR genotyping with I/D flanking primers with an inclusion of DMSO, followed by confirmation of the DD genotype by insertion-specific primers with DMSO, is recommended.
血管紧张素转换酶基因的DD基因型与多种疾病有关。然而，先前报告中的基因型频率有所不同，而且关于DD基因型与疾病关联的数据有时相互矛盾。尽管消除分型错误至关重要，但很少有人对目前采用的分型方法的准确性进行评估。据报道，使用聚合酶链反应（PCR）的常规方法，即带有插入/缺失（I/D）侧翼引物的方法，会出现DD基因型的分型错误。我们调查了目前采用的PCR基因分型方法是否可靠。我们使用带有或不带有二甲基亚砜（DMSO）的I/D侧翼引物，通过常规PCR方法对248名患者进行基因分型，并使用带有或不带有DMSO的插入特异性引物确认DD基因型。分型错误频繁发生，不仅在两种不使用DMSO的方法中如此，在一种改良的使用包含DMSO的I/D侧翼引物的方法中也是如此。事实证明，通过这些方法进行分型比之前认为的更容易导致错误结果。为了降低分型错误频率，建议先用包含DMSO的I/D侧翼引物进行初始PCR基因分型，然后用包含DMSO的插入特异性引物确认DD基因型。
