Joyce BT, et al. - In view of the previous studies suggesting inconsistent associations between blood leukocyte telomere length (LTL) and cancer, researchers investigated if telomere shortening facilitates carcinogenesis. Of 475 participants who provided 889 samples 1-3 times (median follow up: 10.1 years) from 1999-2013 in the Normative Aging Study, 121 developed cancer. Examination of 2,651 CpGs from 80 telomere-related genes (TRGs) yielded 30 CpGs on 23 TRGs whose methylation was positively associated with cancer incidence and one protective CpG in MAD1L1, of which 87% were located in TRG promoters. Cross-sectional association of 3 CpGs with LTL was observed. TRG methylation was thus suggested to be a mechanism through which LTL dynamics reflect cancer risk.