Abstract: Purpose : To establish a nonradio - labelled method for measuring telomere length (mean length of telomere rest riction f ragment , TRF) of human chromosome. Methods : TRF was examined by Southern blotting by using labelled oligonucleotide (CCCTAA) 3 probe with digoxin. After hybridization , the blot was stained with NBT/ BCIP , analysed by using a densitomet ric imaging system and mean length of TRF calculated , comparing with standard kilobase sized marker. Results : The hybridization bands were showed under st ringently cont roling the prode working concent ration (1 :1 280 dilution) , loaded DNA sample ( > 20μg) and hybridization temperature (47 ±2 ℃) Conclusion : A digoxin - labelled , stable , reliable and low background method for determining the telomere length of human chromosome was established.

Key words: telomere, telomere rest riction f ragment, nonradio - label