Rapid gene-maps for newborns promise to cut diagnosis times totwo-and-a-half days for many dangerous genetic ailments, , researchersreported on Wednesday.

Such gene maps, or "whole genome"sequences, take months now, too late or delaying treatment for manyinfants suffering congenital ailments that kill around 5,300 babiesyearly, more than 20% of infant deaths nationwide.

The pilotstudy, at Children's Mercy Hospital in Kansas City, Mo., reportsdiagnosis of genetic diseases in 50 hours' time. The study mapped thegenes of infants with both known and unknown deadly illnesses.

"Fora decade there has been a lot of talk about seeing the human genomeeffort pay off not just in research, but in actually having an impact onhuman health. We may be seeing it happen here," says National Instituteof Child Health and Human Development chief Alan Guttmacher, who wasnot part of the research. "This is an important proof-of-principle studythat needs to be confirmed and repeated by other researchers, but itlooks promising."

In a study reported in the Science Translational Medicinejournal, a genome sequencing team led by Carol Saunders of Children'sMercy Hospital tested rapid genetic diagnosis on two infants with knowngenetic ailments and four suffering unknown ones, three of whom died atthe hospital. Scientists can detect about 3,700 mutations known to causecongenital illnesses, but the rapid test looked for 591 well-understoodones to speed diagnosis. All states must now test newborns for 21common genetic afflictions, such as the brain-damaging ailment PKU.

Inthe pilot study, researchers genetically mapped six ill babies,confirming the two known cases and finding diagnoses for three of thefour unknown cases, as well as the older brother of one child. Theailments had killed three of those children in the unknown diagnosiscases.

"We think this is going to transform the world ofneonatology," says study co-author Steven Kingsmore of Children's MercyHospital, noting the potential for more information and geneticcounseling for parents with desperately ill infants, as well as speedingtreatment to sick babies. "Until now they really had to practicemedicine blindfolded," Kingsmore said.

The roughly $7,000 testrelies on computer diagnostics and a rapid gene sequencing machine madeby the San Diego-based Illumina Inc., which partly funded the study. Thetest costs less than one night in a neonatal intensive care unit,Kingsmore says, which should make its promise of faster treatmentattractive to insurers.

"Insurers will need to run the numbers,but the way that gene sequencing costs are dropping, by the time youfinish the calculation, the costs will have dropped again," saysGuttmacher, who predicts such gene maps will cost $1,000 within the nextfew years. "One can imagine the day that 99% of newborns will havetheir genomes sequenced immediately at birth."