The accumulation of age-associated changes in a biochemical process that helps control genes may be responsible for some of the increased risk of cancer seen in older people, according to a National Institutes of Health (NIH) study.
The emerging field of epigenetics has added a new dimension to the “nature versus nurture” debate, by which researchers have historically attempted to determine whether a characteristic was influenced by genes or environment. Increasingly, it appears that environmental influences can affect gene expression, meaning that “nature” and “nurture” are inextricable from one another to an even greater extent than previously understood.
Researchers have identified a key epigenetic mechanism in the brain that helps explain cocaine’s addictiveness, according to research funded by the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health.
The study, published in the January issue of the journal Science, shows how cocaine affects an epigenetic process (a process capable of influencing gene expression without changing a gene’s sequence) called histone methylation. These epigenetic changes in the brain’s pleasure circuits, which are also the first impacted by chronic cocaine exposure, likely contribute to an acquired preference for cocaine.