Science / Medicine : Genetic Retardation Tests Designed

Doctors in Europe and Australia said last week that they have developed easier ways to detect fragile X syndrome, perhaps the most common cause of inherited mental retardation. The discoveries, reported in the New England Journal of Medicine, are expected to help scientists unravel the complicated pattern of inheritance in the syndrome, which affects the so-called X-chromosome that determines sex. Scientists earlier this year announced the discovery of the defective gene that causes the syndrome.

The work could also help prospective parents assess their risks of having a child born with the syndrome, whose sufferers also tend to be tall, strong, with large ears and a prominent nose and jaw.

One test for a fragile X was developed by European researchers led by geneticist Francois Rousseau of the French research center INSERM. The second was developed by a team led by geneticist Grant R. Sutherland of the Adelaide Children’s Hospital in Adelaide, Australia.