Abstract: 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 pe - ripheral blood cell is needed to be further characterized.Methods One hundred and twenty three periph - eral 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 byχ 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 of5.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 re - stricted fragment length assay.

Key words: telomere, Southern blot, aging