Unlocking secrets

The controversial Human Genome Project -- a collaborative effort to decode and understand the human genetic code in chromosomes -- is already showing results and is likely to be completed ahead of schedule (Nature, Vol 359 No 6394).

The first maps of two human chromosomes -- the long arm of chromosome 21 and the Y chromosome -- have been put together by teams led by Daniel Cohen at the Centre d'Etude du Polymorphism Humain in Paris and David Page at the Massachusetts Institute of Technology in Boston. The maps were prepared by cloning DNA sequences in artificial yeast chromosomes. The Lancet (Vol 340 No 8827) later reported a linkage map of 22 pairs of autosomes (non-sex chromosomes) and the X chromosome has been prepared by researchers at the French Genethon. The map is based on repeated gene sequences that are distributed throughout the genome.

Scientists say the work on the Y chromosome and chromosome 21 demonstrates that a reasonably simple approach can be applied to any genome without constructing complicated chromosome libraries from individual chromosomes.