Gene causing mental disorder found

Scientists have identified a gene responsible for causing microcephaly, a congenital disorder which makes children mentally retarded, giving hopes of identifying it early during pregnancy, a study has said. Researchers from Indian Institute of Science (IISc), Bangalore and National Institute of Mental Health and Neurosciences (NIMHANS) have identified a new gene called 'STIL' which causes the disorder characterised by smaller-than-normal brain size in children.

The study team, comprising Satish Girimaji from NIMHANS and Arun Kumar from IISc's Department of Molecular Reproduction, Development and Genetics, is hopeful that the finding will help in detection of this disorder during pregnancy and counselling of parents about the same. The medical condition is not fatal but leaves a patient mentally challenged throughout his life. Several environmental and genetic factors are responsible for the disorder. The environmental factors include intrauterine infections, alcohol, drugs taken during pregnancy, exposure to radiation of expecting mothers and birth asphyxia.

So far, five genes, including STIL, have been discovered, which cause the disorder. The research published in the latest edition of 'Current Science' will also help in the study of evolution of human brain from the days of hominids, who had smaller brains similar to a microcephaly patient.