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Daniel J. DeNoon
WebMD Health News
Reviewed By Louise Chang, MD
The clue comes from the observation that smokers aren't the only people who age too fast. In their 20s, people with a rare genetic disorder called Werner's syndrome get gray hair, thin skin, and hoarse voices.
Yes, say University of Iowa researchers Toru Nyunoya, MD, and colleagues.
Werner's syndrome is caused by a mutation in a gene called WRN. The gene makes the WRN protein that protects and repairs DNA in every cell of the body.
Nyunoya and colleagues collected lung cells from smokers with emphysema. Sure enough, the cells had too little WRN protein. The smokers' WRN genes were normal, but something was keeping them from making enough WRN.
When the researchers cultured lung cells in the laboratory, they found that cigarette smoke extract decreased the cell's WRN production -- and made the cells age more quickly. Cells genetically engineered to make too much WRN were not as strongly affected by the smoke extract.
The findings appear in the Feb. 6 issue of the American Journal of Respiratory and Critical Care Medicine.
SOURCES: Nyunoya, T. American Journal of Respiratory and Critical Care Medicine, Feb. 6, 2009; vol 179: pp 279-287. News release, University of Iowa. News release, American Thoracic Society. National Library of Medicine Genetics Home Reference, "Werner Syndrome," accessed online Feb. 5, 2009.
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