A conservative view on the state of knowledge of telomeres and related biochemistry can be found in this paper: "Telomeres, the termini of linear chromosomes, consist of large but variable numbers of DNA oligomer repeats embedded in a nucleoprotein complex. In humans, telomere length (TL) is largely genetically determined but also featured by an age dependent attrition. TL has therefore been put forward as a marker for biological aging and was also reported to be associated with aging diseases such as cardiovascular disease. However it remains unclear whether the biomarker value in a particular disease depends on shorter TL at birth or rather if it's a mere reflection of an accelerated telomere attrition during lifetime, or else, if it is a combination of both. While the importance of telomere attrition is supported by cross-sectional evidence associating shorter telomeres with oxidative stress and inflammation, longitudinal studies are required to accurately assess telomere attrition and its presumed link with accelerated aging." A number of research groups and companies are working on safe ways to change telomere length, with the aim of impacting age-related disease or aging itself.