人类外周淋巴细胞中21号染色体不分离随年龄增长而增加。

Increased nondisjunction of chromosome 21 with age in human peripheral lymphocytes.

作者信息

Shi Q, Chen J, Adler I, Zhang J, Martin R, Pan S, Zhang X, Shan X

机构信息

Institut fuer Saeugetiergenetik, GSF Forschungszentrum fuer Umwelt und Gesundheit GmbH, Neuherberg, Germany.

出版信息

Mutat Res. 2000 Jul 20;452(1):27-36. doi: 10.1016/s0027-5107(00)00032-4.

DOI:10.1016/s0027-5107(00)00032-4

PMID:10894887

Abstract

Fluorescence in situ hybridization (FISH) on binucleated cells with chromosome-specific DNA probes provides a convenient way to visualize reciprocal segregation patterns in daughter nuclei, and overcomes most problems related to the artefactual loss or gain of chromosomes that flaw chromosome preparations. In this study, FISH was employed to evaluate age- and sex-effects on spontaneous malsegregation, nondisjunction and loss of chromosome 21 in human lymphocytes after the first division in culture. A total of 68 healthy nonsmokers and nondrinkers of alcohol (37 males and 31 females) were grouped by age as Group I (0-10 years), Group II (20-30 years), Group III (40-50 years) and Group IV (60-70 years), with at least seven subjects per group and sex. FISH with a pericentric chromosome 21 specific DNA probe was carried out on binucleated lymphocytes, cytokinesis-blocked by cytochalasin B (6 microg/ml for 26 h) at 44 h after initiation of cultures. Linear regression analyses demonstrated a significant age-related increase in the frequency of micronuclei without chromosome 21 (MN-21)(r=0.73, p<0.001 in females; r=0.69, p<0.001 in males) in all binucleated cells, with a steeper slope in females (0.1758) than in males (0. 1241). Analysis using the 2x2 chi-square (chi(2)) test on the frequencies of MN-21 showed significant age-related differences in both males and females, except males in Group III and Group IV (p>0. 05). A significant sex-related difference was found only in subjects over 60 years (p<0.05), with females having more MN-21 (12.57 per thousand vs. 8.43 per thousand) than males. Loss of chromosome 21, occurring at mean levels of 0.38 per thousand in all binucleated cells and 0.24 per thousand in binucleated cells containing four FISH signals, was shown not to be age- or sex-related. A positive age-related increase in nondisjunction of chromosome 21 was shown in males (r=0.50, p<0.01), females (r=0.61, p<0.001) and all subjects (r=0.55, p<0.001) by linear regression analysis. An age effect was found only between children and adults (p<0.01 for females, p<0.05

摘要

使用染色体特异性DNA探针，对双核细胞进行荧光原位杂交（FISH），为观察子核中的相互分离模式提供了一种便捷的方法，并且克服了与染色体人为丢失或增加相关的大多数问题，而这些问题会影响染色体标本质量。在本研究中，采用FISH评估年龄和性别对人淋巴细胞培养首次分裂后21号染色体自发错分、不分离和丢失的影响。共有68名不吸烟且不饮酒的健康受试者（37名男性和31名女性）按年龄分为四组：第一组（0 - 10岁）、第二组（20 - 30岁）、第三组（40 - 50岁）和第四组（60 - 70岁），每组至少有7名不同性别的受试者。在培养开始44小时后，用细胞松弛素B（6微克/毫升，作用26小时）阻断胞质分裂，然后对双核淋巴细胞进行21号染色体着丝粒特异性DNA探针的FISH检测。线性回归分析表明，在所有双核细胞中，与21号染色体无关的微核（MN - 21）频率随年龄显著增加（女性r = 0.73，p < 0.001；男性r = 0.69，p < 0.001），女性的斜率（0.1758）比男性（0.1241）更陡。对MN - 21频率进行2×2卡方（χ²）检验分析表明，除第三组和第四组男性外（p > 0.05），男性和女性的MN - 21频率均存在显著的年龄相关差异。仅在60岁以上的受试者中发现了显著的性别差异（p < 0.05），女性的MN - 21更多（千分之12.57对千分之8.43）。21号染色体的丢失在所有双核细胞中的平均水平为千分之0.38，在含有四个FISH信号的双核细胞中的平均水平为千分之0.24，未显示出与年龄或性别相关。线性回归分析表明，男性（r = 0.50，p < 0.01）、女性（r = 0.61，p < 0.001）和所有受试者（r = 0.55，p < 0.001）中，21号染色体不分离随年龄呈正相关增加。仅在儿童和成年人之间发现了年龄效应（女性p < 0.01，男性p < 0.05）