Several months back, we reported in our blog that the authorities that regulate IVF and other fertility procedures in the UK were considering allowing IVF with mitochondrial transfer to move forward. Mitochondrial transfer is more popularly known as “three parent IVF,” because it involves three genetic parents: the woman who provides her chromosomes, the husband who provides his chromosomes and the donor who provides the mitochondria which contain their own DNA. The HFEA in the UK has now given the green light for tightly regulated research to proceed on mitochondrial transfer. So, now it is likely that fertility researchers in Britain will move forward and learn whether this technique can help couples with mitochondrial diseases.
Most of the genetic material in our cells is contained in the chromosomes which we inherit as a mixture from our mothers and fathers, but not all of it. A small amount of DNA is found in the mitochondria, the little structures in our cells that act like batteries. The only way to prevent the transmission of the genetic diseases of the mitochondria to date in couples who wants their own genetic children has been through the use of donor egg IVF. The problem is with donor egg is that the baby receives no genetic material from the the mother, and that only way around that problem would be to move the nucleus (which contains mom’s genetic material) from the mother’s egg into a donor egg. That process is called nuclear transfer and was banned by the US government because it involves cloning technologies. Now the FDA is considering lifting the ban to allow research into IVF with nuclear transfer for mitochondrial diseases. If successful, this would create babies with 3 genetic parents for the first time, a genetic mother, a genetic father and a mitochondrial mother. Quite a bit to ponder.
It has been known for some time that couples suffering from infertility, including those who get pregnant using assisted reproductive techniques such as IVF, are more likely to have complicated pregnancies.: more high blood pressure, diabetes, miscarriages, preterm births and likely birth defects as well. This is true even with singleton pregnancies. What is not so clear is why this is so. Is it the patient population? Women who have infertility tend to be older and have more medical and metabolic problems. Is it the fertility medications such as clomid and injectables? Is it something in the process of IVF or IUI that causes problems? Researchers at Cedars Sinai Hospital in Los Angeles have received a large grant from the National Institute of Child Health and Development to help study the molecular events the underlie an early pregnancy after IVF. They will be looking at both genetics (the DNA in the chromosomes) and epigenetics (changes in gene expression that occur outside the chromosomes) to try to discover an explanation for these problems