Getting to gray hair’s roots
With enough time, every blonde, brunette, and redhead goes silver, but scientists had been unable to pin down the cellular basis behind gray hair. By examining two strains of mutant mice, however, researchers finally have unveiled a root cause for this inevitable part of aging.
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Mice with mutations in either of two genes, known as Bcl2 and Mitf, go gray months faster than normal mice. After analyzing hair follicles from both mutant strains, David Fisher and his colleagues at Harvard Medical School in Boston found some telling activity in stem cells within each follicle’s base.