An Indian-origin scientist reportedly identified a chemical signal in the zebrafish brain, which helps it in regenerating retina, may help to cure blindness in humans. The scientists tested their hypothesis in two ways firstly, by blinding zebrafish and injecting them with drugs that stimulate gamma-aminobutyric acid(GABA) production and secondly, by injecting normal zebrafish with an enzyme that lowers the GABA levels in their eyes.