To ask Her Majesty’s Government, further to the Written Statement by the Parliamentary Under-Secretary of State for Public Health, Jane Ellison, on 17 December 2014 (HC Deb, col. 96WS), what concerns were raised by the expert panel convened by the Human Fertilisation and Embryology Authority (HFEA) regarding the possibility of carryover of a small percentage of abnormal mitochondrial DNA (mtDNA) from the affected oocyte or zygote as a result of close associations between mtDNA and the karyoplast; what additional consideration the HFEA’s expert panel gave to replicative advantage of some mtDNA variants skewing the proportions in subsequent development as a result of a mitochondrial bottleneck; whether they can therefore guarantee that no females born following spindle-chromosomal complex transfer or pronuclear transfer would ever transmit the disease to subsequent generations; if not, whether serial nuclear transfer would minimise this risk; and why serial nuclear transfer is precluded by Regulations 3(c) and 6(c) of the Draft Human Fertilisation and Embryology (Mitochondrial Donation) Regulations 2015, which prevent any further “alterations in the nuclear or mitochondrial DNA”.
- mitochondrial DNA carryover at sections 3.7.2 to 3.7.11;- nuclear-mitochondrial interactions at sections 3.7.15 to 3.7.20; and- points relating to replicative advantage and mitochondrial bottleneck are widely discussed throughout section 3.
The Panel’s report is attached.
The HFEA has also advised that the Expert Panel it convened concluded that, following Maternal Spindle Transfer or Pronuclear Transfer, the risks of mitochondrial disease in the next generation will be low. Further details can be found in section 3 of the Panel’s 2014 report.
Serial nuclear transfer is not a term or process connected with mitochondrial donation. Therefore, serial transfer is not something the Expert Panel has considered.
This Answer included the following attachment:
HFEA's Panel Report (HFEA Panel's Report.pdf)