Parents who are at risk of having children with serious genetic disorders sometime choose IVF (in vitro fertilisation) followed by preimplantation genetic diagnosis (PGD) using polymerase chain reaction (PCR) to increase their chances of having a healthy baby. However, this involves removing one or more cells from the developing embryo in a biopsy, which could increase the risk of failure. Researchers from the UK and Italy have found that PCR can diagnose genetic disorders in early embryos without the need of a biopsy.
Blastocysts are 5-6 day old embryos of 50-300 cells around a blastocoele, a fluid-filled cavity. The team took samples from this fluid and, using PCR, found that 90% of the samples contained cell-free DNA from the embryo. They were also able to amplify the genes TSPY1 (on the Y chromosome) and TBC1D3 (on chromosome 17), which suggests that it could be used to screen for male embryos, which are at higher risk of X-linked disorders.
This is the first time that embryonic DNA has been detected in the human blastocyst without the use of biopsy, according to the researchers.
Chromosome abnormalities are one of the main causes of failures and miscarriages during IVF treatment. According to the researchers, whole genome amplification and DNA microarrays could be used on these samples to confirm that embryos had a normal number of chromosomes. The research was published in Reproductive Biomedicine Online.
“More work needs to be done to confirm our results, but we hope that this approach will ultimately help infertile couples achieve their dream of having a family. It may also improve the options for families affected by severe inherited conditions, helping them to have healthy babies,” says Professor Magnani of the University of Urbino.
Suzanne Elvidge is a freelance science, biopharma, business and health writer with more than 20 years of experience. She has written for a range of online and print publications including FierceBiomarkers, FierceDrugDelivery, European Life Science, the Journal of Life Sciences (now the Burrill Report), In Vivo, Life Science Leader, Nature Biotechnology, New Scientist, PR Week and Start-Up. She specialises in writing on pharmaceuticals, biotechnology, healthcare, science, lifestyle and green living, but can write on any topic given enough tea and chocolate biscuits. She lives just beyond the neck end of nowhere in the Peak District with her second-hand bookseller husband and two second-hand cats.