Researchers here find a disconnect between DNA methylation patterns shown to correlate well with age and processes associated with longer telomere length. Telomeres are caps of repeated DNA at the ends of chromosomes that shorten with each cell division, a part of the mechanism limiting the life span of somatic cells. Their average length tends to shorten with age when considered across large populations in a statistical analysis, but this is a tenuous relationship that has also failed to appear in some smaller studies. Here, it seems that older ages as assessed by DNA methylation can correlate with differences in telomerase, the enzyme responsible for lengthening telomeres, that are associated with longer telomeres.
In any given individual, average telomere length as currently measured in leukocytes from a blood sample is dynamic in response to circumstances; it reflects pace of cell division and the rate at which new cells with long telomeres are generated by stem cells. Unfortunately the large degree of individual and circumstantial variation means that there is little to be meaningfully said about the present value – the information is not actionable in all but rare cases of exceptionally short average length due to
Article originally posted at