Positioned as the endcaps of chromosomes, telomeres are involved in the processes of genetic replication and stability.  In that critically short telomeres lead to replicative cell senescence and chromosomal instability, previous studies have suggested that telomere length is an emerging marker of biological age.  To study telomeres in leukocytes, a type of blood cell, Peter Willeit, from Innsbruck Medical University (Austria), and colleagues conducted PCR (polymerase chain reaction) testing of 787 men and women enrolled in the Bruneck Study in Italy, each of whom were cancer-free in 1995 at the study’s start. The team followed the subjects for 10 years, tracking cancer incidence and mortality. Analysis indicated that short telomere length at the beginning of the study was associated with new cancer independently of standard cancer risk factors. Compared with participants in the longest telomere length group, participants in the middle length group had about twice the risk of cancer, and those in the shortest length group had approximately three times the risk. Cancer incidence rates were inversely related to telomere length, with participants in the group with the shortest telomere length having the highest rate of cancer.  The team notes that short telomere length was also associated with a higher rate of death from cancer, and conclude that: “there was a statistically significant inverse relationship between telomere length and both cancer incidence and mortality.”