An in vitro fertilization (IVF) milestone has been announced by British researchers. For the first time, a baby was born using a new embryo screening technique combs through genetic data looking for risk for diseases and other abnormalities. The researchers say the technique, known as "next generation sequencing" will revolutionize embryo selection for families turning to IVF.}
"In the past few years, results from randomized clinical trials have suggested that most IVF patients would benefit from embryo chromosome screening, with some studies reporting a 50 percent boost in pregnancy rates. However, the costs of these genetic tests are relatively high, putting them beyond the reach of many patients," lead researcher Dr. Dagan Wells, a scientist at the NIHR Biomedical Research Centre at the University of Oxford in the U.K., said in a statement. "Next generation sequencing is a way which could make chromosome testing more widely available to a greater number of patients, improving access by cutting the costs."
Wells presented the case study of the first birth Monday at the European Society of Human Reproduction and Embryology in London.
Next generation DNA-sequencing technology is used in other areas of medicine, such as in research of differences between normal cells and cancer cells, according to the Columbia Genome Center in New York City. For the process, DNA is broken into small fragments which are turned into strings of genetic code which are then sequenced in hundreds of millions parallel reactions.
This testing can also reveal information on the chances for inheriting genetic disorders, chromosome abnormalities and mitochondrial disease, mutations within a cell's nucleus that could lead to conditions including heart disease, motor disorders, diabetes, respiratory problems, seizures, and vision and hearing problems.
Wells said since the technology is already revolutionizing diagnostic medicine, if it's applied to embryo selection for IVF, it can provide "an unprecedented insight into the biology of embryos."
That's important, because only about 30 percent of embryos currently selected for transfer in IVF actually implant in the uterus. The reason for this high failure rate is unknown, according to the researchers, but they suspect hidden genetic mutations and abnormalities may be at play.
To ensure the new technique's accuracy, the researchers sequenced cells from 45 embryos that had previously been shown to be abnormal by a different testing technique. In a blind comparison of the two techniques, high accuracy was established.
Wells' team then conducted the sequencing on two women under 40 who were to undergo IVF, and found three chromosomally healthy cells it would use in the embryo transfer. The researchers conducted single-embryo transfers based on the findings, and both mothers became pregnant, with the first giving birth to a healthy baby boy in June.
Wells' research found next generation sequencing could produce genetic information that revealed abnormalities that are linked to miscarriage, while at the same time identifying risk for other serious gene defects. The technique also accomplished this in only about 16 hours, avoiding the need to freeze the embryo while results were analyzed.
IVF can be costly, with the average U.S. price for one cycle about $12,400, WebMD reported. Embryo-screening is an expensive add-on to IVF, the researchers added, saying this new technique could cut costs by two-thirds.
"Many of the embryos produced during infertility treatments have no chance of becoming a baby because they carry lethal genetic abnormalities," said Wells. "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."
The child's parents, Marybeth Scheidts, 36, and her husband David Levy, 41, told the BBC they had been trying to conceive naturally for more than four years, and also tried artificial insemination. Scheidts said if she had undergone a different kind of genetic testing in the States, it would have cost her $6,000.
"It takes its toll, there were some days I would break down and cry, I wanted to hide in my bedroom and say stop," she told the BBC of her time trying to conceive. "Then to see him... all this hard work and we have finally got our little tiny human being named Connor."
Wells and fellow researchers expressed caution to New Scientist that the technique should not be used for trivial, non-medical reasons such as predicting hair color or the shape of facial features.
"The fact that something is scientifically and technically possible doesn't necessarily mean that it should be done," said scientist Manfred Kayser of Erasmus Medical Centre in Rotterdam, the Netherlands.
Concerns over parents choosing so-called "designer babies" also appeared last week in the U.K. after the country's National Health Service (NHS) said it was going to present to Parliament a proposal forin newborns. In that process, one percent of DNA comes from a donor.