不同年龄组白细胞端粒DNA长度变化研究

目的探讨人外周血白细胞端粒DNA随年龄变化的规律。方法选取123例不同年龄健康人外周血样本,采用非同位素探针标记的SouthernBlot方法检测了端粒DNA限制性酶切片段(Telomericre鄄strictedfragment,TRF)长度的变化。结果对这123例样本就性别组成进行χ2检验,得出P>0.05,说明这123例样品性别对TRF的差异不显著。123例外周血白细胞端粒TRF平均长度随年龄增长而逐渐缩短,且TRF随年龄缩短的速度是不均一的,人外周血白细胞染色体端粒DNA长度可能在5岁左右存在缩短加剧现象。对0～14岁、15～64岁及≥65岁三组进行方差分析(SNK检验),显示有显著性差异(P<0.01)。结论不同年龄组人外周血白细胞端粒DNA长度具有显著差异且变化速率不同,该研究结果为通过端粒DNA长度推断个体年龄提供了可能。

Study on the dynamic changing profiles of telomeric restricted fragment length among sex balanced different age groups

OBJECTIVE: In human, both in vivo and in vitro, telomere shortening appears to be a major component of cell senescence and aging. The detailed telomere shortening status and mechanism in peripheral blood cell is needed to be further characterized. METHODS: One hundred and twenty three peripheral blood samples were collected from healthy individuals of different age groups and the mean telomeric restricted fragment (TRF) was measured using Southern Blotting with Dig labeled probe. The samples of different groups were homogenized in sex components as indicated by chi 2 test of sex ratio of different test groups (P > 0.05). RESULTS: The average length of TRF is shortening with aging and distinguished shortening dynamic profiles could be observed. Further analysis showed that there might be a shortening peak near the age of 5. CONCLUSION: There are distinguished dynamics profiles of telomere shortening among different age groups. Thus, the results indicate that it might be possible to infer individual age by telomeric restricted fragment length assay.