Dr Jonathan Beckwith, American biologist, examining a petri dish containing a genetically- engineered colony of the bacteria, Escherischia coli, in his laboratory at Harvard Medical School. As a respected scientist working with genetic engineering technology, Beckwith is concerned about the social & legal implications of human genetic screening, an option that might arise from the successful completion of the human genome project - an ambitious plan to make a complete biochemical survey of every gene expressed on all the 23 pairs of human chromosomes. Photographed May 1989.