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Mitochondrial Disease

Volume 565: debated on Tuesday 25 June 2013

It is a great pleasure to serve under your chairmanship, Mr Davies. I am pleased to be able to lead a debate on this most important subject. I shall speak about mitochondrial disease, the devastation it causes and the new techniques developed by Newcastle university to prevent it. I declare an interest in that my father studied medicine at Newcastle, so I am a natural champion of that great university’s medical research and innovation. I am here primarily to champion not Newcastle university however, but the interests of my constituents struck down by mitochondrial disease, and indeed all those who suffer from it.

The subject is technical and I will attempt to be as clear as possible in setting out the arguments. Mitochondria are found in every cell in the human body, except red blood cells. They are the batteries generating energy for the cell. Mitochondria convert the energy of food molecules into the energy that powers the cell’s functions. About 200 children are born every year with a mitochondrial disease. Such diseases are passed from mothers to their children and are caused by faulty mitochondria. Like all DNA, the DNA in mitochondria can mutate and mothers can pass those mutations on to their children. Faulty mitochondria mean that the cells are unable to function normally and the diseases caused by them can have a devastating effect on families. The diseases tend to affect parts of the body that use a lot of energy, such as the brain, muscles, nerves, liver, kidney and heart, and vary widely in severity, from life-threatening to having few or no obvious symptoms. Symptoms vary, but can include poor growth, muscle weakness, tiredness, poor co-ordination, and sensory, respiratory or cognitive problems.

There are no effective treatments available for serious mitochondrial disease. When the cells go wrong, it can result in serious conditions, including blindness, fatal heart failure, liver failure, learning disabilities and diabetes, and can lead to death in early infancy. Prevention is the only realistic option. In 2010, Newcastle university scientists, with funding from the Wellcome Trust, pioneered research into variations of in vitro fertilisation procedures that could prevent the transmission of the genetic mutations that cause these devastating disorders. The techniques use part of an egg donated by a healthy individual, to replace the faulty mitochondria of the affected mother. The intention is to give affected families a chance to have healthy children that are genetically related to them, but born free of mitochondrial disorders. Such techniques are not currently permitted in the UK, but legislation allows the Government to introduce secondary legislation that would allow the treatments to be used.

Mitochondrial disease can blight families for generations, because, as I said, it is passed from the mother to child during pregnancy. The techniques could put a stop to it, by preventing the faulty mitochondria from being passed to the embryo. Mitochondrial disease affects about 6,000 adults in the UK. In my constituency, four families—Bumstead, Cass, Bland and Mahmood—suffer from mitochondrial disease. Although every effort is being made to help them, there is no cure. For example, Lily Cass, who is in her 70s now, has five brothers and three sisters, and one brother who died at 56. They are all affected in different ways by mitochondrial diseases, and some more severely than others. Some days, Lily can hardly move due to lack of energy caused by her faulty mitochondria, which takes all her strength away. She has four children, including a daughter, who is likely to pass the disease on to her children. She worries about that all the time.

For those women and their families, the most important help we can offer is potential treatments, to prevent the next generation of patients from being affected. The opportunity to have their own children free of disease is something that the patients understandably want.

As with all such advances, it is right that the ethics are properly considered before techniques are adopted, and the Minister will be aware that concerns have been raised. There are those who argue that the techniques create children with three parents, but the embryo would carry only a small number of genes from the donor—just 13 out of 23,000, or 0.056% of the genetic material. How much of a parent is that? The function of the 13 genes is restricted to powering the mitochondria; they do not affect personal characteristics such as eye or hair colour, or behaviour.

Last June, the Nuffield Council on Bioethics produced a report that found that the technique would be an ethical treatment option for affected families, as long as research showed that treatment was likely to be safe and effective, and families were offered full information and support. The council’s report found that no strong cultural or social emphasis is generally placed on mitochondrial inheritance as a specific element of personal identity. Many of the social and biological aspects that typically imply a “parent”, and may be relevant in egg donation for reproduction, do not apply to mitochondrial donation. The council therefore suggested that if the treatments were made available, mitochondrial donors should not have the same status in regulation as reproductive egg donors.

My hon. Friend makes a good case about the serious effects that the diseases resulting from the condition have on families. If we think forward to any children who are fortunate enough to be born without disease because of the treatment, would there be any possibility that they might consider themselves to have three parents, whether or not they had any traits from the third one? Has thought been given to how that would be considered if it should happen?

My hon. Friend is right. There has been some debate about the status not only of the donors but, most importantly, of the children. The Nuffield Council on Bioethics says that families must be offered full information and support, and that must also apply to the children, so that they understand the scientific nature of the very limited gene inheritance from the donation.

If mitochondrial donors were not given the same status as reproductive egg donors, it would be not legally required for them to be identifiable to people born from their donations. The council concluded that the proposed treatments would be a form of gene therapy that would permanently cure the disease in future generations. Changes resulting from the replacement of mitochondrial DNA would be passed on not only to the resulting children, but to the descendants of any girls born from the techniques, via their eggs.

Dr Geoff Watts, who chaired the inquiry, said:

“We understand that some people concerned about the idea of germline therapies may fear that if such treatments for mitochondrial gene disorders were approved, a ‘slippery slope’ would be created towards comparable alterations to the nuclear genome.”

That is an understandable fear, but he went on to make a very important point:

“However, we are only talking about the use of these techniques in the clearly-defined situation of otherwise incurable mitochondrial disorders, under strict regulation.”

In 2012, the Human Fertilisation and Embryology Authority—HFEA—launched a public consultation on mitochondria replacement. It interviewed almost 1,000 people, and a further 1,800 completed questionnaires. It also organised public workshops around the UK and spoke to individuals affected by the diseases, to gauge their views. It published the results in March of this year, and found broad public support for the use of the technique.

The HFEA asked four main questions about attitudes to the gene treatment of mitochondrial diseases. When asked about attitudes to the selection of embryos based on testing, 65% of those questioned were positive or very positive, with only 8% negative. When asked about altering the genetic make-up of an egg or an embryo, 56% were positive or very positive and only 10% were negative. Attitudes to the use of genetic material from a third person showed that 44% were positive or very positive, with only 15% negative. The HFEA therefore advised the Government that there was broad support for mitochondrial replacement being made available to families at risk of passing on a serious mitochondrial disease. It also advised that if treatment were to be authorised by Parliament, it should be under certain conditions, such as its being available only in licensed clinics.

The HFEA recommendations have been widely welcomed by campaigners. For example, Dr Marita Pohlschmidt, director of research at the Muscular Dystrophy Campaign, said:

“We welcome this outcome. There is currently no effective treatment available for mitochondrial diseases, and at this time, prevention remains our strongest option. By taking forward research into pro nuclear IVF, we move towards giving women living with these devastating and unpredictable conditions the choice to bear their own unaffected children. This technique does involve a step into new scientific territory. But it is a calculated, specific step with the sole aim of preventing a potential fatal condition from being passed down to the next generation, where possible.”

We are now waiting for a decision from the Government about whether secondary legislation that will allow the techniques to be licensed for use in patients will be introduced in this parliamentary Session. It has taken years to get to this stage, and it is important that progress does not stall because families are waiting for this. Introducing regulations now will ensure there is no avoidable delay in the treatments reaching affected families once research is completed and the HFEA considers there to be sufficient evidence that the techniques are safe and effective.

I called this debate to hear an update from the Minister on the progress that she has made, and to ask when we can expect a decision, and when we can expect to see legislation.

It is a pleasure to serve under your chairmanship, Mr Davies. I congratulate the hon. Member for Newcastle upon Tyne Central (Chi Onwurah) not only on securing the debate but on highlighting the impact of mitochondrial disease on families, and the potential of the new techniques to prevent suffering and premature death and bring hope to the many families who seek to prevent their children from inheriting these sorts of diseases in the future. The hon. Lady does everyone a service in raising the issue. It is a controversial issue, and she has asked me some direct questions.

The Government fully recognise the sensitivity of the issues, and since researchers first approached my Department in 2010 requesting that we make regulations, we have been collecting expert opinion and public views. I will be up front, and say straight away that the chief medical officer has given the issue her careful consideration in the light of the advice and the findings of the Human Fertilisation and Embryology Authority, following the consultation period. I anticipate that she will set out the Government response before the summer recess and, even with my poor mathematics, I can work out that that should certainly be within the next few weeks.

I emphasise that the Department of Health has given careful consideration to the advice and information passed to us by the Human Fertilisation and Embryology Authority on 28 March. We have also taken account of other published reviews, such as the one in 2012 by the Nuffield Council on Bioethics in its report on “Novel techniques for the prevention of mitochondrial DNA disorders: an ethical review”.

Our considerations are being led by the chief medical officer. It is right, if we are to move forward, that she should be the person to lead on the proposals—she may reject them—and, as the CMO, to make any announcement and to be at the forefront of any decision. I am told that her considerations are almost complete.

We recognise that allowing the treatment would give an opportunity for women who carry mitochondrial disease the choice—it is important to state that if regulations are introduced, they would have a choice—to have genetically related children without the risk of serious diseases; I am grateful to the hon. Lady for giving examples of those diseases, and it is the understandable desire of many parents, especially women, not to allow them to be inherited by a child.

This issue is about giving women a choice on whether or not their DNA is put into another woman’s egg. In effect, a woman would be hijacking the batteries, because mitochondria are the batteries that provide the energy, and when they do not work, they cause these diseases. This is not about any kind of genetic engineering, about which people would rightly be concerned.

When the science and the real benefits are explained to people, and the fact that the child who is born has the same genetic background as their mother, they will see that the press have perhaps been a bit misleading in saying that, if it all goes ahead, some children will have three parents. They really will not: they will have their biological mother and father. It is simply that the batteries have been taken from another woman’s egg so that they are sure that any child does not bear some of the very serious diseases that often lead to premature death.

We recognise the concerns that have been raised about whether such techniques are a form of germline or genetic modification in human beings and about whether it would be ethical to allow them in treatment, and those considerations are important. Technically, the resultant embryo would be formed from the eggs of two women, but the genetic material that relates to the child’s characteristics would have been removed from the donor egg, so the child will have genes from the patient and her partner—in other words, from the child’s mother and father—but they will also have healthy mitochondria.

I thank the Minister very much for the constructive form of her response and for the new information. Her point about the child not having the genetic material is very important. Will she emphasise that the process is nothing like changing the eye colour or height of the unborn child? An important point to get across is that there is no genetic modification in that sense.

I absolutely agree. I am perhaps putting the subject in simple terms, but that is how it is. This is actually about the fact that if someone is effectively carrying this particular disease, the mitochondria—the batteries that charge things—are replaced to make sure that they do not have these diseases. Because the mitochondria cannot be taken out of the mother’s egg, a donor egg has to be found. The DNA is removed from that egg and the mother’s DNA is put in—taking those good healthy mitochondria or the batteries—so that she has a healthy egg that, in due course, can be fertilised by the father in the normal way. It is absolutely right that the genetic make-up of a resultant child will be the mother’s and father’s. That does not of course guarantee that the child will have the same colour eyes as their mother, as we all know, especially me as a blue-eyed mother with two brown-eyed daughters. As ever, Mr Davies, I digress, but this is a serious matter.

I pay great tribute to researchers at the International Centre for Life in Newcastle. The hon. Lady should not hesitate to do so, whether her father was there or not, because it is a fine institution. They have been developing their groundbreaking expertise for many years. In anticipation of significant advances in this field, the Human Fertilisation and Embryology Act 1990 was amended in 2008 to introduce a regulation-making power that, if implemented, would enable mitochondria replacement to take place in treatment.

The powers are therefore there, but it is important to say that they would not be implemented in some secondary way. I understand that the matter would have to come to this place and that, in any event, there would be a debate. That is my understanding, but if I am wrong I will correct that, as you would expect, Mr Davies.

In 2010, Newcastle researchers approached the Department of Health and, in the light of their progress, requested that we consider introducing regulations to allow mitochondria replacement in treatment. In response, the Department asked the Human Fertilisation and Embryology Authority to get independent advice about the safety and efficacy of the techniques.

An expert advisory group was established, and a report was passed to the Department in spring 2011. It found that the techniques were not unsafe, but it recommended that further research be undertaken. After careful consideration of that report, the Department of Health and the Department for Business, Innovation and Skills commissioned the HFEA in autumn 2011 to undertake a comprehensive set of public consultations to identify the public’s views about and understanding of this complex and sensitive issue. That consultation was held between July and December last year. It looked at the social and ethical issues raised by mitochondria replacement, as well as addressing a range of practical regulatory issues.

In collaboration with Sciencewise, which has a key role in helping the public to understand complex scientific issues, the HFEA took many different approaches to ensure that it gathered public views on the issue. It held workshops with members of the public, tracking their views over time and in response to new information. It ran what is called a representative survey, an online public consultation, two public meetings through which interested groups and individuals could express their views, and a focus group with families who are personally affected by mitochondrial disease, because their views are extremely important.

The HFEA report was published on 28 March and was passed to the Department. It provided us with three separate strands of advice: the outcome of its public dialogue and consultation; a scientific update on the safety and efficacy of the new techniques; and the issues to consider in introducing an appropriate regulatory framework. The public consultation indicated, overall, that there is general support for allowing the treatment techniques to be used, as long as they are safe and carefully regulated.

We appreciate and recognise, however, that a range of views, not all of which were in favour of a change in regulation, was strongly expressed through the consultation. A significant response came from the religious community, which was not in favour of allowing the techniques, whereas the scientific community, bioethics groups and patient and family groups were in favour.

The expert panel, which was reconvened by the HFEA, concluded that although there continues to be nothing to indicate that the techniques are unsafe, further research on some specific aspects should be undertaken. All the recommended research is currently being undertaken either in Newcastle or Oregon in the United States. The expert panel expressed the view that insufficient research is currently available to recommend one particular technique above another. It also recommended long-term follow-up monitoring of any children born as a result of the techniques.

I conclude where I began by saying that we anticipate that the CMO will announce the Government’s response very soon—before we break for the recess—which is at least some good news. As the hon. Lady said, the issue has been ongoing for several years, so it is important to find out whether it will reach the sort of conclusion that she wants, and we anticipate that that will be very soon.

Sitting suspended.