If you change your hair color more frequently than Lady Gaga, you may be affecting your DNA methylation patterns, according to a new study in the journal Epigenetics.
To gain a better understanding of the “normal” human methylome, researchers used BeadChip arrays to analyze the methylation of 26,486 CpG loci in the blood of 205 healthy volunteers. Then, they examined relationships among methylation patterns, CpG sequence features, aging, and environmental exposures such as UV, smoking, and hair dye use. Here’s what they found:
- Aging did not significantly influence CpG island methylation, but overall DNA methylation and the methylation of several repeat sequences decreased with age.
- Of the environmental exposures, only hair dye use showed a statistically significant association with DNA methylation.
- Those who frequently hit the hair dye bottle showed greater methylation of CpG islands and decreased methylation of highly methylated sequences such as LINE-1.
These findings demonstrate the importance of considering CpG context when analyzing relationship between aging or environmental exposures and DNA methylation, the researchers say. They note that although some environmental exposures didn’t seem to affect methylation patterns in peripheral blood, they may show tissue-specific effects.
Get all the hair-raising details at Epigenetics, July 2011.