Recently, Moshe Szyf, a McGill University epigeneticist, performed a series of experiments indicating that chemical marks on people’s brain cells can reveal suicidal tendencies long before these people consider taking their own lives.
To start, Szyf and his colleague Michael Meaney compared two types of rats: those that received frequent licking and grooming as pups, and those that had been neglected as newborns by their deadbeat moms. Motherly love, they found, altered DNA methylation levels in the regulatory regions of the glucocorticoid receptor (GR) gene in the brains of young rats. These epigenetic changes, in turn, affected the regulation of stress hormone levels into adulthood, such that licked pups matured into calmer adults than their less-groomed, jittery counterparts (Nat Neurosci, 7:847–54, 2004).
Szyf had discovered a way in which the early environment stably altered the genome for the rest of a ...
