Coolbaugh-Murphy Mary I, Xu Jingping, Ramagli Louis S, Brown Barry W, Siciliano Michael J
Department of Molecular Genetics, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe, Houston, TX 77030, USA.
Mech Ageing Dev. 2005 Oct;126(10):1051-9. doi: 10.1016/j.mad.2005.06.005.
Small pool PCR (SP-PCR) is a sensitive method for the detection and quantification of microsatellite instability (MSI) in somatic cells. Here we propose that mutant microsatellite fragments accumulate with age in normal somatic cells and that this increase in MSI can be quantified by SP-PCR. MSI at 6 microsatellite loci was determined by SP-PCR in PBL DNA from 17 "normal" blood bank donors. These individuals varied in age from 20 to 67 y/o. MSI phenotypes were plotted against age in a regression analyses. A positive slope indicated a correlation between age and MSI phenotype (p=0.0006). The mean weighted average mutant frequencies across all loci for all individuals in the age groups (0.009 for 20-30 y/o; 0.019 for 35-50 y/o; 0.034 for 60-70 y/o) were also significantly different from each other (p<0.01). A baseline for increases of MSI with age in human somatic cells was therefore begun and the effectiveness of SP-PCR to evaluate low, but significant, levels of MSI, established.
小池聚合酶链反应（SP-PCR）是一种检测和定量体细胞中微卫星不稳定性（MSI）的灵敏方法。在此我们提出，突变微卫星片段在正常体细胞中会随年龄积累，且这种MSI的增加可通过SP-PCR进行定量。通过SP-PCR测定了17名“正常”血库供者外周血淋巴细胞（PBL）DNA中6个微卫星位点的MSI。这些个体年龄在20至67岁之间。在回归分析中，将MSI表型与年龄作图。正斜率表明年龄与MSI表型之间存在相关性（p = 0.0006）。各年龄组所有个体所有位点的平均加权平均突变频率（20 - 30岁组为0.009；35 - 50岁组为0.019；60 - 70岁组为0.034）彼此之间也存在显著差异（p < 0.01）。因此确定了人类体细胞中MSI随年龄增加的基线，并证实了SP-PCR评估低水平但显著的MSI的有效性。
