Journal of Genetic Syndromes & Gene Therapy
Open Access

Abstract

Telomere Length and Telomere-related Genetic Variations in Epidemiology: Getting the Context Right

Fernando Pires Hartwig

Telomeres (5? TTAGGG 3? DNA tandem repeats and associated proteins) are in the spotlight of biomedical research given the body of evidence linking them with physiological aging and aging-related diseases, including tissue self-renewal failure (and consequences of this in several organs) and cancer. The epidemiological method has been extensively applied to study telomere biology in mainly two contexts: telomere length measurement and genotyping genetic variants associated with telomere length. Although both methods have the same common goal of better understanding the roles of telomeres in health and disease, they greatly differ regarding applications and limitations. In this manuscript, both methods are compared regarding common issues in causal inference: reverse causation, confounding, effect mediation and discerning a causal factor from a biomarker. In conclusion, telomere length measurement and genotyping genetic proxies can be combined to increase robustness, although some applications required the dynamics of telomere length, thus requiring robust study designs. In addition, the use of an appropriate conceptual framework can assist both data collection and analysis in many situations.