Papadopoulos Nickolas
GMP Genetics, Inc, Waltham, MA, USA.
Expert Rev Mol Diagn. 2003 Jul;3(4):497-506. doi: 10.1586/14737159.3.4.497.
Identification of germline mutations in a sensitive and specific manner presents a continuing challenge. A major contributing factor to this is that humans are diploid and therefore mutations in one allele are often masked by the normal sequence present on the other copy of the chromosome. Mutation analysis on haploid templates (one copy of a chromosome), rather than on diploid templates (both copies of a chromosome), overcomes this problem and obscured mutations are unmasked. Conversion technology converts a sample from diploid to haploid state by isolating individual alleles in somatic cell hybrids. From each sample, a series of stable hybrids is generated that contains the human chromosome complement in the haploid state. This article describes conversion technology and its applications. The utility of this technique in increasing the sensitivity of genetic testing has been demonstrated for the predisposition to hereditary nonpolyposis colorectal cancer and it is proposed that a similar approach may be applicable to many different diseases.
以敏感且特异的方式鉴定种系突变一直是一项挑战。造成这一情况的一个主要因素是人类是二倍体，因此一个等位基因中的突变常常被染色体另一条拷贝上的正常序列所掩盖。对单倍体模板（一条染色体的一个拷贝）而非二倍体模板（一条染色体的两个拷贝）进行突变分析，克服了这个问题，使被掩盖的突变得以显现。转换技术通过在体细胞杂种中分离单个等位基因，将样本从二倍体状态转换为单倍体状态。从每个样本中生成一系列稳定的杂种，这些杂种包含单倍体状态的人类染色体组。本文描述了转换技术及其应用。该技术在提高遗传性非息肉病性结直肠癌易感性基因检测的灵敏度方面的效用已得到证实，并且有人提出类似方法可能适用于许多不同疾病。
