A new study has suggested that Down's Syndome in a child might one day be treatable before the birth of the child, in the womb itself.

Researchers have based their claims on an experiment on mice. In the experiment they injected two key nerve-protecting chemicals into pregnant mice with Down's pups and found that the offspring turned out to be free of these problems.

Down's syndrome in humans is caused in children who inherit an extra copy of chromosome 21 while mice engineered to have a similar condition are given an extra copy of a segment of chromosome 16. In both the cases the development of certain motor and sensory abilities is delayed.

However, when the researchers at National Institutes of Health in Maryland injected the proteins - NAP and SAL - into mice pregnant with trisomic pups in the middle of their pregnancy they found that the newborn pups reached developmental milestones such as grasping a rod, righting themselves and responding to tactile stimulation at the same time as normal mice.

Also, the brain of the mice showed normal levels of ADNP - one of the regulatory proteins under-produced by Down's-affected glial cells - and of another compound that is a marker for healthy glial cells.

According to the researchers, both these outcomes indicate that some effects of Down's had been removed.