Magazine article Science News

Same Difference: Twins' Gene Regulation Isn't Identical

Magazine article Science News

Same Difference: Twins' Gene Regulation Isn't Identical

Article excerpt

Although identical twins have identical DNA, they often harbor clear-cut differences: slight variations in appearance or stark distinctions in disease susceptibility, for example. Scientists have suggested that the interplay between nature and nurture could explain such differences, but the mechanism has been poorly understood.

A new study suggests that as identical twins go through life, environmental influences differently affect which genes are turned on and which are switched off.

Called epigenetic modification, such gene activation or silencing typically stems from two types of chemical groups that latch on to chromosomes as charms attach to a bracelet, says Manel Esteller of the Spanish National Cancer Centre in Madrid. Methyl groups that clip on to DNA tend to turn genes off. On the other hand, acetyl groups attaching to histones, the chemical core of chromosomes, usually turn genes on.

Suspecting that such epigenetic differences might account for variations between identical twins, Esteller and his team focused on the two chemical changes. The scientists recruited 80 pairs of identical twins, ranging in age from 3 to 74, from Spain, Denmark, and the United Kingdom.

After extracting DNA from blood, inner-cheek cells, and biopsied muscle, Esteller's team screened the twins' genomes for differences in epigenetic profiles between members of a pair. The researchers also had each twin or, for children, a parent answer a comprehensive questionnaire on the twins' health history and lifestyle, including diet, exercise habits, and alcohol or tobacco use. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.