Scientists Map Chromosome 5

GENETICS experts reported today that they had mapped Chromosome 5 of the human genome, a coil of DNA linked to several rare but crippling disorders including spinal muscular atrophy. The 22 pairs of human chromosomes, together with the X and Y chromosomes that determine gender, were unravelled in a long-term sequencing project that ended in April 2003. The task since then has been to sift through the raw data to analyse each of the chromosomes, notably seeking out genes and genetic variations blamed for inherited disease. So far, a dozen chromosomes have been sequenced and analysed in this way. In their study, which appears tomorrow in the British journal Nature, scientists led by Jeremy Schmutz of the Stanford Human Genome Centre in California said Chromosome 5 measures 177.7 million base pairs -the "rungs" of matched chemical compounds that make up a spiral of DNA.