Following yesterday's post on changing gene expression with brain waves, I'll point to another bit of work on gene changing. Chemical changes to DNA, mainly methylation, can alter gene expression in response a number of environmental changes such as stress, diet, and pollutants. Reynolds points to work by Lindholm et al. now showing that exercise activates health enhancing genes by this epigenetic mechanism. They use the simple trick of measuring and comparing methylation of DNA in exercised and unexercised legs of single individuals (twentythree young subjects bicycled using only one leg, leaving the other unexercised, for three months. The pedaling was at a moderate pace for 45 min, four times per week for three months.) Not surprisingly, the exercised leg was more powerful, but in addition more than 5,000 sites on the genome of muscle cells from the exercised leg now featured new methylation patterns.
This work makes me wish I had a home kit for detecting methylation change in the DNA of my thumb muscles, which show dramatic changes in strength and size depending on how often and energetically I practice the piano.