Public in favour of allowing mitochondrial replacement, says UK regulator
26 March 2013
Mitochondrial replacement therapy, where a small amount of a mother's genetic material is swapped with material from a donor during IVF to avoid passing on heritable illnesses, enjoys the 'general support' of the public, the UK's fertility regulator says.
Presenting the findings of its public consultation, 'Medical Frontiers: Debating Mitochondria Replacement', Professor Lisa Jardine, chair of the Human Fertilisation and Embryology Authority (HFEA), said: 'The Government has asked us to take the public temperature on this important and emotive issue and that is what we've done. We've found that there is broad support for permitting mitochondria replacement, to give families at risk of mitochondrial disease the chance of having a healthy child'.
Mitochondrial replacement is a term describing two techniques - maternal spindle transfer and pronuclear transfer - which could potentially be used to avoid the transmission of mitochondrial disease. The Government is considering whether to change the law so that these techniques, which are currently only allowed in a research setting, could be used clinically.
The HFEA decided on its advice to government in light of both the consultation findings and the latest evidence regarding the safety and efficacy of the techniques.
The HFEA will advise that any regulation permitting germline genetic modification (where any alterations would be passed on to subsequent generations) should be formulated so as to permit mitochondrial replacement exclusively, 'in order to address concerns that permitting these techniques might open the door to other less desirable ones'.
The regulator will also say that mitochondrial replacement should be permitted only 'to avoid serious mitochondrial diseases in cases where clinical specialists have deemed it to be appropriate'. The HFEA will propose that it licenses mitochondrial replacement on a case-by-case (rather than condition-by-condition or centre-by-centre) basis to begin with, but that it should have the option of changing this regime in future if it so wishes.
The HFEA will advise that donors of mitochondria 'should have a similar status to that of tissue donors', and that people conceived using mitochondrial replacement 'should not have a right to access identifying information about the donor'.
It was thought, however, that people conceived using mitochondrial replacement should be able to access non-identifying information about the donor, and also that donors and people conceived using their donation should be helped to contact and identify one another by 'mutual consent' if this is something both parties desire.
Given that research into both techniques is ongoing, the HFEA will propose that a further scientific review of safety and efficacy should take place if and when the first application is received for a licence to perform mitochondrial replacement.
'We understand that more research is required but believe it is crucial that the government moves now to draft the regulations so that mitochondrial patients in the UK will have access to this treatment', said Professor Doug Turnbull, director of the Wellcome Trust Centre for Mitochondrial Research at Newcastle University.
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02 May 2013
Director of IVF Laboratory, M.D., Ph.D.
Fact Sheet: Not Suitability of Mitochondria Injection into Human Eggs to Produce Babies
1. Point 1,2,3,5,6,7 in the “Fact Sheet Re: Not Suitability of Ooplasm Transfer” (submitted by Ke-Hui Cui to FDA on Dec.22, 1999, www.fda.gov/ohrms/dockets/dailys/00/jan00/010300/c000217.pdf) are still suitable for this fact sheet.
2. Human mitochondria DNA contain 37 genes, in which 13 genes involve producing energy (ATP). The remaining genes provide instructions for making amino acids into proteins. The types and ratio of these genes and their dosage in human eggs are important to be remained to avoid any kind of mitochondrial diseases. Mitochondria injection (including autologous injection with mitochondria extracted from egg precursor cells) will change the types, ratio, dosage, morphology, metabolic activity, cell origin (i.e. not oocyte per se) and location of these different mitochondrial genes, which will lead to hereditary mitochondrial diseases1.
3. Mutation rate of mitochondrial DNA is higher than that of nuclear DNA if human cells are under abnormal condition or even under normal condition. Any in vitro procedures including cell culture and any extraction procedures, reagents and temperature variations will easily lead to mitochondria DNA mutation1 as these procedures will lead to nuclear DNA mutation. Injection of those mitochondria with mutation will lead to higher rate of hereditary diseases.
4. All of the artificial eggs created from reprogrammed stem cells in human and animal research in recent 10 years showed abnormal functions although with normal morphology. These incomplete reprogramed eggs and their precursor cells (or egg stem cells) are full of mitochondria with abnormal methylation condition and abnormal histone code. Injection of reprogramed mitochondria will lead to genetic diseases3.
5. Mitochondria injection in eggs will not change energy supply in the eggs due to most mitochondrial regulators to be controlled by nuclear DNA1 rather than by mitochondria DNA itself.
6. Mitochondria injection in the eggs will lead to babies’ phenotype (or trait) to be changed2, 3. The main reason is: anything influences the eggs or sperm will lead to changes in the babies’ phenotype3. Detailed reason are:
A. Environmental change can change phenotype of human beings even after birth. The human sperm count and quality are getting worse in recent 20-30 years is an obvious example, (according to WHO data).
B. Food and medicine can change phenotype of human beings before birth. Lack of folic acid will lead to fetal abnormality is an example.
C. Environmental change can change phenotype of human beings at the embryonic stage. Water and air quality, temperature, pH, amino acid, ion concentration, etc. will change embryo development, including DNA degeneration, cell number and embryo morphology, later miscarriage rate and stillbirth rate, etc.
D. Any change happened in eggs and sperm will change phenotype of human beings. PVP used in ICSI (Intracytoplasm Sperm Injection) injected into the eggs will lead to sex chromosome abnormalities in babies is an example. Also, more human albumin in ICSI into the human eggs will lead to worse embryo development is another example. If injecting genes into the human eggs, hereditary diseases will follow.
E. The phenotype sensitivity to any change in human beings is closely related to age: the younger, the more sensitive. Phenotype sensitivity to environmental change: Egg > Sperm > Embryo > fetus > babies > adults.
7. There is feedback system3 in egg stage, as the same as in embryonic stage and after birth (such as hormone feedback system). Proteins, RNA and DNA in ooplasm will commute with nuclear DNA1, to let nuclear DNA to re-control the concentration and function of proteins, RNA and DNA again3. Embryos in no calcium and magnesium medium during embryo biopsy over 30 minutes will lead to the born baby mice with higher blood calcium and magnesium is a good example of the feedback results. Injection with mitochondria into the eggs will lead to the nuclear DNA recognizes too much of mitochondria, thus regulates the genes to produce less mitochondria in babies, which will lead to the babies to get mitochondrial diseases2. There are 37 mitochondria genes. Thus mitochondria injection into the eggs will lead to more than 37 kinds or up to different combination of mitochondrial diseases.
8. Set up an animal research group to test mitochondria injection with number of 100 births up to 5-10 generations with all mitochondria injection to compare with a control group, a significant difference will be found immediately to confirm the safety problem (from all kinds of phenotype change to DNA dosage and ratio change).
9. Mitochondrial diseases usually are late-onset diseases1, which include different kinds of cancer, neuropathy, diabetes, epilepsy, deafness, growth development problem, function problems of heart, brain and muscles, and etc. They are rare diseases, and hard to be diagnosed and hard to be treated.
10. No insurance company can cover IVF and these late-onset genetic disease together. It means that the physician performing mitochondria transfer by ICSI may be facing bankruptcy if the patient sues him for the created genetic disease.
11. For the aim to solve patient’s infertile problem, it is not worth changing human beings.
12. In reverse, if the future daughter of babies from mitochondria injection wishes to change back to normal mitochondria condition as her grand mom’s mitochondrial condition, can anyone help her to solve her problem? Her problem is more severe than the infertile problem. The answer is: no one can help her to solve the genetic problems which has been created. How about the daughter’s offspring and offspring? No hope. Disaster!!! Human beings have been changed and can not be changed back to be normal3. The transgenerational effect is of deep concern.
1. Human mitochondrial genetics – Wikipedia.
2. Int. J. Epidemiol 41 (1): 177-187, 2012.
3. Epigenetics – Wikipedia.