May 22, 2011
Longevity? Telomere DNA Testing Raises Criticism
The telomere theory of cell lifespan and mortality has been widely considered significant - measure the lengths of the ends of the chromosomes (telomeres) and correlate that length to cell age - it was the basis for the 2009 Nobel Prize awarded to Dr. Elizabeth Blackburn, Dr. Carol Greider and Dr. Jack Szostak for this work. One could predict that commercial genetic testing to exploit this mechanism for predictive value - biological age? - would ensue. Several companies are in the race to offer such testing: Telome Health was co-founded by Blackburn to develop such testing. Life Length (Spain) has just announced such a test for sale for about $700. The causal relationship between telomere length and cell lifespan is still being researched; what's interesting is that the commercial interest in offering genetic tests that capitalize on the initial observations has been immediate. The Food and Drug Administration (FDA) does not generally regulate genetic tests in the marketplace unless the test is offered as a kit, rather than a laboratory service. That means that most genetic tests are not regulated or reviewed. However, things are changing. The FDA has formed an advisory committee, the Molecular and Clinical Genetics Panel of the FDA's Medical Devices Advisory Committee, which is to study how the FDA should step in, particularly regarding the direct-to-consumer (DTC) tests being offered. The FDA has outlined a set of questions that are to be considered by the expert panel, focusing on the risk assessment, evidentiary burdens, and how the lack of professional intermediation creates more dangers for patients using DTC tests for medical decisions. One question also notes that individuals often seek such tests for lifestyle reasons or personal interest (e.g., longevity?) and asks whether those more casual objective should alter the measures of scientific performance for these tests. Of note is the criticism of such commercial testing from Dr. Greider, the opposition by the American Medical Association to the offering of DTC genetic tests without the supervision of a health professional.