| Popis: |
Mitochondrial diseases represent the most common inborn errors of metabolism. The overwhelming majority of mitochondrial diseases (about 85 %) are caused by mutations of nuclear genes of oxidative phosphorylation. The remaining 15 % are caused by mtDNA mutations. The familial mtDNA mutations are exclusively inherited from the mother. Dysfunction of oocyte mitochondria is believed to result in poor developmental competence of oocytes in older infertility patients. Therefore, a group of patients underwent ooplasmic transfer from fertile donor oocytes to rejuvinate their developmentally compromised oocytes. However, this series was stopped, because two foetuses were affected by Turner’s syndrome and a second issue was related to the risks of mitochondrial heteroplasmy. Instead treatments with heterologous mitochondria, autologous transfer has been introduced instead. However, interim analysis of a controlled randomised trial has shown that autologous germline mitochondrial energy transfer is not a feasible treatment to improve embryo quality in IVF. For the prevention of the transmission of mtDNA mutations in principle four methods are available: preimplantation genetic diagnosis (PGD) or prenatal diagnosis (PND) followed by the selection of the best embryo or foetus; the use of complete donor oocytes; mitochondrial replacement therapy (MRT) and genome editing. Not each of these is applicable in reproductive medicine yet. The stage of development will be discussed. |
