外周血白细胞特定染色体相对端粒长度的测定

Measurement of chromosome-specific relative telomere lengths in peripheral leukocytes

目的:建立一套以相对长度为单位的测量人类单个染色体端粒长度的标准,测定正常人特定染色体长臂和短臂末端上的端粒长度。方法:采用荧光原位杂交定量法(Q-FISH)测定所有单个染色体端粒的信号强度,并转化为相对端粒长度(relative telomere length,RTL)进行比较。结果:对20例正常人外周血白细胞每条染色体上RTL值的测定显示,不同染色体臂上的端粒长度呈非随机分布并差异有统计学意义(F=8.923,P<0.01),其中2q、16p、17p、17q、19p、20q、22q、Yq的端粒最短(P<0.05),而3p、5p、Xp和Yp的端粒最长(P<0.05)。结论:用Q-FISH测定单个染色体RTL的方法易标准化,便于推广;正常人外周血白细胞中46条不同染色体上的端粒长度呈现特定的分布模式。

Objective：To established a relative telomere length（RTL） -based common standard for the measurement of single telomere lengths in human chromosomes,investigate the length distribution and variation among chromosome-specific telomeres in 20 normal people.Method：Using quantitative fluorescence in situ hybridization（Q-FISH） ,the fluorescence intensity of each single telomere was detected,then converted to an RTL,thus the RTL can be compared.Result：Telomere lengths at different chromosome end showed a nonrandom distribution statistically（F=8.923,P0.01） .The RTL at chromosome ends of 2q,16p,17p,17q,19p,20q,22q,Yq were shorter than others（P0.05） ,and the RTL at 3p,5p,Xp and Yp（p：chromosome short arm,q：chromosome long arm） were longer（P0.05） .Conclusion：It is easy to generate RTL using fluorescence intensity of the QFISH to determine chromosome-specific telomere length,which can be standardized and analyzed.There was specific distribution on chromosomes telomere length.