IVF gene-screen success

The baby boy was born in June in the US state of Pennsylvania, with a second woman who underwent the screening process due to give birth shortly.

The technique, known as next generation sequencing or NGS, uses low-cost modern DNA sequencing to reveal inherited genetic disorders, chromosome abnormalities, defects and mutations, before the embryo is implanted into the womb.

In-vitro fertilization, when eggs are fertilized with sperm in a laboratory, has a relatively low pregnancy success rate after implantation - around 30 percent. While it's not known why the failure rate is so high, genetic defects are high on the list of suspects, according to the authors of research being presented on Monday at the annual meeting of the European Society of Human Reproduction and Embryology (ESHRE).

"Many of the embryos produced during infertility treatments have no chance of becoming a baby because they carry lethal genetic abnormalities," said study author Dagan Wells, from the University of Oxford's NIHR Biomedical Research Center.

"Next generation sequencing improves our ability to detect these abnormalities and helps us identify the embryos with the best chances of producing a viable pregnancy," Wells said.

ESHRE says one in six couples worldwide experience some form of infertility problem at least once in their lifetime.

In addition, the new technique could be significantly cheaper than current technology and yield more genetic data than older methods.

"We can do this at a cost which is about a half to two-thirds of what current chromosome screening costs are," said Wells.

"If further randomized trials confirm this, we could reach a point where there is a very strong economic argument that this should be offered very widely - perhaps to the majority of IVF patients."

According to Wells, the method has started to be used in genetic research and diagnostics, but not in embryo screening.

He said that current methods to detect gene deficiencies in embryos added more than £2,000 (2,300 euros, $3,000) to a single IVF attempt.

"The new method should allow costs to be reduced by several hundred pounds, potentially bringing the benefits of chromosome screening within the reach of a far greater number of patients," said Wells, describing how he tested the technique on an "abnormally high" number of embryos until he was satisfied of a high level of accuracy.

A randomized clinical trial is due to begin later this year to determine the technique's efficacy.

jr/ccp (Reuters, AFP)