Telomeres consist of tandem repeats of (TTAGGG)n DNA sequence and associated proteins including those of the shelterin complex. Telomeres are essential nucleoprotein structures conserved in all vertebrate species aiding in chromosome stability and genome integrity and are hence related to cell senescence and cancer.
This study was carried out to the quantify the amount of telomeric DNA and establish age prediction equations use the quantity of telomeic DNA for cattles. Analysis of the telomere quantity of the lymphocytes was performed at different age, across breeds and between sex of cattles.
We quantified the amount of telomeric DNA by the Q-FISH technique using the telomeric DNA probe in 460 cattles at an age range of 1∼166months belonging to the Korean cattle and Holstein.
In results, we found that the amount of telomeric DNA decreased along with age. Quantity of telomeric DNA was significantly higher in Korean cattle than the Holstein breed. In addition, the amount of telomeric DNA in male Korean cattle was significantly higher than that in females.
Although each treatment showed significant difference, the amount of telomeric DNA however decreased along with age in all cattle. Using this relationship between age and the amount of telomeric DNA in cattle, we hereby establish age predicting equations as a result of regression analysis where X is quantity of telomeric DNA and Y is predicted age in months.
Korean cattle (male) Y = 23.291X² - 142.763X + 223.201
Korean cattle (female) Y = 38.102X² - 220.103X + 318.309
Holstein (female) Y = 42.799X² - 199.682X + 242.106
The above equations predict the age of cattle at high significance and accuracy with high R square value (0.68∼0.84). Thus, our study makes it possible to scientifically predict age using the above equations for male, female Korean cattle, and female Holstein cattles.