MODEL RELEASED. Human genome research. Researchers Dr Nigel Carter and Sheila Clegg studying a FISH micrograph of chromosomes marked to reveal the presence of genes for the Human Genome Project. FISH (fluorescence in situ hybridisation) allows genes (green and red) to be marked on a chromosome to confirm their positions. Genes are lengths of DNA (deoxyribonucleic acid) which control specific functions in an organism. The human genome project aims to find the DNA sequence of all human genes. This will allow for improved drug design and a greater understanding of genetic diseases. Photographed at the Sanger Centre in Cambridge, England.