The epidemiology of human telomeres: faults and promises.

There are neglected but growing problems in the epidemiological field of telomere biology. The focus of the field has been on leukocyte telomere dynamics, which ostensibly register the accruing burden of oxidative stress and inflammation. Important as they are, studies that have examined associations between leukocyte telomere length and indices of aging and diseases of aging also include many that are compromised by poor epidemiological and laboratory methodology. The shortcomings of these studies muddle findings, undermine conclusions, and compromise the ability of the field to attain its goals, which include a better understanding of human aging. Specific steps are delineated to resolve these problems. They include a call for an impartial evaluation of the two major methods (Southern blots and quantitative polymerase chain reaction) currently in use to measure telomere parameters and a proposal for a working model to test the potential connections of leukocyte telomere dynamics with human aging and longevity.