Study finds alterations in genes tied to immune system and brain development, but whether they cause the disorder remains unclear. (p. 9)

A genetic mistake causes misinterpretation of epigenetic marks, leading to cancer. (p. 11)

One study finds tissue-specific methylation signatures in the genome; another a similarity between identical twins in DNA’s chemical tagging. (p. 5)

As identical twins go through life, environmental influences differently affect which genes are turned on and which are switched off. (p. 19)

Team finds differences related to metabolism and growth. (p. 15)

Pollutant exposures in rodents can have behavioral repercussions that persist generation after generation. (p. 198)

Early exposure to bisphenol A, a building block of polycarbonate plastics, can trigger a variety of later health problems. (p. 84)

Don’t dismiss Lamarck Your January 31 special birthday edition on Darwin (SN: 1/31/09, p. 17) was excellent, but I believe that science has allowed Jean-Baptiste Lamarck’s contributions to be overshadowed by Darwin’s. The change that can occur to an organism’s genetic makeup during its own lifetime harks away from Darwin’s slow evolutionary process by chance mutations and argues toward Lamarck’s heritable changes within a lifetime. Robert Powell, Austin, Texas Take a vote of biologists today and Darwin will win hands down. But I predict that in 20 years that will ch... (p. 30)

Study finds a lack of chemical tags near a prostate cancer gene in African American males. (p. 13)

Scientists have known for ages that metabolism is tied to the body’s daily rhythms. Two new studies suggest how.

The way genes are packaged by "epigenetic" changes may play a major role in the risk of addiction, depression and other mental disorders.

epigenetic changes can be undone in some circumstances.