In genetic diseases for which treatments exist, rapid diagnosis is critical for neonatal interventions that lessen morbidity and mortality. (Photo: Sarah Maxey Photography)
Rapid gene-maps for newborns promise to cut diagnosis times to
two-and-a-half days for many dangerous genetic ailments, , researchers
reported on Wednesday.
Such gene maps, or "whole genome"
sequences, take months now, too late or delaying treatment for many
infants suffering congenital ailments that kill around 5,300 babies
yearly, more than 20% of infant deaths nationwide.
The pilot
study, at Children's Mercy Hospital in Kansas City, Mo., reports
diagnosis of genetic diseases in 50 hours' time. The study mapped the
genes of infants with both known and unknown deadly illnesses.
"For
a decade there has been a lot of talk about seeing the human genome
effort pay off not just in research, but in actually having an impact on
human health. We may be seeing it happen here," says National Institute
of Child Health and Human Development chief Alan Guttmacher, who was
not part of the research. "This is an important proof-of-principle study
that needs to be confirmed and repeated by other researchers, but it
looks promising."
In a study reported in the Science Translational Medicine
journal, a genome sequencing team led by Carol Saunders of Children's
Mercy Hospital tested rapid genetic diagnosis on two infants with known
genetic ailments and four suffering unknown ones, three of whom died at
the hospital. Scientists can detect about 3,700 mutations known to cause
congenital illnesses, but the rapid test looked for 591 well-understood
ones to speed diagnosis. All states must now test newborns for 21
common genetic afflictions, such as the brain-damaging ailment PKU.
In
the pilot study, researchers genetically mapped six ill babies,
confirming the two known cases and finding diagnoses for three of the
four unknown cases, as well as the older brother of one child. The
ailments had killed three of those children in the unknown diagnosis
cases.
"We think this is going to transform the world of
neonatology," says study co-author Steven Kingsmore of Children's Mercy
Hospital, noting the potential for more information and genetic
counseling for parents with desperately ill infants, as well as speeding
treatment to sick babies. "Until now they really had to practice
medicine blindfolded," Kingsmore said.
The roughly $7,000 test
relies on computer diagnostics and a rapid gene sequencing machine made
by the San Diego-based Illumina Inc., which partly funded the study. The
test costs less than one night in a neonatal intensive care unit,
Kingsmore says, which should make its promise of faster treatment
attractive to insurers.
"Insurers will need to run the numbers,
but the way that gene sequencing costs are dropping, by the time you
finish the calculation, the costs will have dropped again," says
Guttmacher, who predicts such gene maps will cost $1,000 within the next
few years. "One can imagine the day that 99% of newborns will have
their genomes sequenced immediately at birth."
USA Today