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Researchers find behavioral evidence of personality genes in babies LOS ANGELES (May 24, 1998 11:03 p.m. EDT http://www.nando.net) -- Even by the age of two weeks, babies are more alert and exploratory if they have a "novelty-seeking" gene that may influence sensation-seeking in adults, researchers reported Sunday. Babies with the gene DRD4 were more likely to follow a red ball with their eyes, respond to a human face and pay attention to the sound of a rattle than other babies, according to an Israeli study of 81 infants just two weeks after birth. "Some of the reason they do that is because of a particular form of a gene," said lead researcher Richard P. Ebstein, a molecular geneticist and laboratory director at the Sarah Herzog Memorial Hospital in Jerusalem. The newborns' response to their surroundings "seems to be based on the same genetic (variation) as an adult," Ebstein said. "A child who even at two weeks reacts strongly to stimuli, seems to be alert, doesn't get scared, doesn't freeze in the crib -- that same person at 20 years old is willing to go mountain climbing, biking and drive his car too fast." An outside observer was skeptical of the study even though he said the theory was plausible. "The sample sizes are much too small to be confident of these results," said James Swanson, a pediatrics professor who heads the Child Development Center at the University of California, Irvine, where he specializes in attention deficit hyperactivity disorder. The novelty-seeking gene is controversial because some studies have failed to find a link to personality while others have indicated connections to addiction and hyperactivity. But Ebstein said his results suggest that early genetic and behavioral tests could be used to detect personality traits, help steer children's psychological development and even drive career choices. The study appears in the May issue of the journal Molecular Psychiatry. Ebstein, who previously studied the gene in adults, believes he is seeing evidence of the role genetics plays in influencing a person's temperament. Experts believe genes and environment each contribute about 50 percent to personality. By using newborns, Ebstein and colleagues at the hospital and at Ben-Gurion University of the Negev in Beersheba, Israel, attempted to weed out some environmental factors. DRD4 is a variation of one of the genes for a part of brain cells called a dopamine receptor. One brain cell signals another by releasing the chemical dopamine, which then attaches to receptors on the receiving cell. The dopamine system is responsible for movement, may be involved in learning and rewards and has been implicated in addiction. Some babies who had the "novelty-seeking" gene but lacked a so-called "neuroticism" gene -- believed by some to influence anxiety and harm avoidance -- showed even stronger novelty-seeking behavior, Ebstein found. Babies with the neuroticism gene but no novelty-seeking gene were more cautious. "You might not want to have somebody who's a super-sensation seeker, coupled with low neuroticism ... flying Boeing planes or driving a Greyhound bus," Ebstein said. By Jane E. Allen, AP Science Writer Copyright 1998 Nando.net Copyright 1998 The Associated Press janet paterson aka calendar control supervisor 51/10 - sinemet/selegiline/prozac - [log in to unmask] quotations: http://newww.com/cgi-bin/do_cal?c:newvoice pwp event calendar: http://newww.com/cgi-bin/do_cal?c:pwpc