New Embryonic Test Raises Concerns

British researchers have revealed a new embryo screening advance that could help more couples avoid the risk of having children with severe genetic disorders.

The new analysis technique, which is similar to DNA fingerprint work used by police, was developed by the Guy's and St. Thomas' NHS Foundation Trust, which is made up by two of London's oldest teaching hospitals.

Experts hope it will improve the reliability and success rate of such screenings for families watching out for diseases like cystic fibrosis, sickle cell and spinal muscular atrophy.

"This is a step in the right direction," Dr. Alan Copperman, the director of infertility at the Mount Sinai School of Medicine in New York, said Monday. "The next step of testing for hundreds, if not thousands of diseases, will hopefully be available in the next few years."

The standard screening test, known as pre-implantation genetic diagnosis or PGD, helps identify specific mutations in genes. The new work, which is called Preimplantation Genetic Haplotyping, is essentially a new way of analyzing the data to zero in on chromosomal "markers" in DNA.

"Because the markers act like a DNA fingerprint, it gives us a more accurate diagnosis," Alison Lashwood, a consultant nurse in genetics and PGD who worked with the team who developed the new technique.

Such "fingerprinting" enables the scientists to distinguish between the chromosomes carrying the affected genes and those which do not. The work is applied to a relatively small percentage of the population who are genetically predisposed to such diseases, Lashwood said.

The work, which was published in peer-reviewed Reproductive BioMedicine Online, was presented in Prague, Czech Republic, during the European Society of Human Reproduction and Embryology's 22nd annual conference.

Though most couples are fertile, they would use IVF — treatments such as those used by infertile couples, the trust said in a statement. A single cell is extracted from each embryo — which at the time is only eight cells in all — and analyzed to compare against those embryos which carry the genetic disorder and those that do not.

The unaffected embryos are then transferred in hopes of a pregnancy without the genetic condition, the trust said. It said five pregnancies had been achieved so far.

News of the advance ignited debate among ethicists in Britain, some of whom fear that doctors have taken another step on the slippery slope toward having "designer babies" — or children meeting the parameters of parental specifications.

"It would be a bad thing if it meant less money were going to be put into research for cures for these same conditions," said Paula Boddington, a philosopher and senior research fellow at the Institute of Medical Genetics at Cardiff University's medical school. "You're never going to screen out all of them."

But doctors who work in the field stressed that all the tests do is help people make decisions about their future — and that of their families.

"All these techniques do is help people have healthier babies," Dr. Jamie Grifo, the program director of the New York University Fertility Center. "It's not about the master race."

Other physicians, such as Dr. Mark Hamilton, the chair of the British Fertility society, said that the tests are focused on debilitating diseases, rather than trying to select for eye color or other similar genetic characteristics.

"I think in the public mind there's the notion that you could use this technology that you can use this to screen for something other disease," Hamilton said. "It's not the case. One should be absolutely clear."