Len Seymour: This is only the beginning of what gene therapy can do

Share
Related Topics

The compelling simplicity of gene therapy attracts great attention, with interest swinging between enthusiastic optimism when there is dramatic progress and scathing criticism when things go badly. Calling it "gene therapy" does imply the approach will work (it's written on the tin), but it has been a long and difficult road towards success.

The University College London/Moorfields study is a welcome step forward. It highlights the principle that gene therapy can be used to improve vision in some patients with Leber's congenital amaurosis, giving hope where there was none before. Hope is contagious and many people with incurable genetic diseases will be interested in these findings, hoping that gene therapy treatments may soon be found for them. Gene therapy can work, but only when the healthy "transgenes" can be introduced efficiently into diseased cells. The biggest step in turning principle into practice occurred when scientists appreciated the need to prioritise efficient "transgene delivery". In the case of the Moorfields study, the transgenes are delivered using a vector – a harmless virus that "infects" the diseased cells – injected directly under the retina.

Similar effects have been seen once before, at Great Ormond Street Hospital, in the treatment of children with severe combined immune deficiency (SCID); the "bubble boys". There, vectors were administered to bone marrow stem cells isolated from patients, and then reintroduced so that they can repopulate the patients' immune systems with healthy cells.

In all cases, it's about efficient transgene delivery, and we anticipate continued success in other areas where diseased target cells can be accessed directly – for example by injection in the treatment of Parkinson's disease, or by treatment of stem cells in other immune disorders.

Although animal research is essential for most forms of medicine, clinical trials are particularly important to assess strengths and weaknesses of complex approaches like gene therapy. For example, the toxicities seen in four patients with SCID (where the transgene became inserted into the patients' chromosomal DNA and caused leukaemia) were not anticipated from preclinical studies. Only because some patients were enrolled in experimental trials have we now learnt the importance of making safer vectors for SCID, and future trials will be conducted using these new vectors. SCID is a life-threatening disease, and for patients without bone marrow donors, gene therapy now provides a remarkable, potentially curative, way forward.

Applying gene therapy to diseases where target cells are spread around the body, for example in cancer, requires development of more sophisticated vectors that can be injected into the patients' bloodstreams and can seek out and deliver therapeutic transgenes selectively to the target diseased cells. That is the area where much of gene therapy research is now focused, and progress in delivery will undoubtedly lead to even more exciting breakthroughs, including in the treatment of some of the major killers of our time – cancer and heart disease.

Len Seymour is professor of gene therapies at Oxford University and president of the British Society for Gene Therapy

React Now

Latest stories from i100
Have you tried new the Independent Digital Edition apps?
SPONSORED FEATURES
iJobs Job Widget
iJobs General

Recruitment Genius: New Business Client Manager - OTE £35,000

£18000 - £35000 per annum: Recruitment Genius: This global technology company ...

Recruitment Genius: Account Manager - Telecoms - OTE £23,000

£20000 - £23000 per annum: Recruitment Genius: An exciting opportunity has bec...

Recruitment Genius: Front of House Team Member

£18000 per annum: Recruitment Genius: This strategic outsourcing and energy se...

Recruitment Genius: IT Support Engineer

£18000 - £26000 per annum: Recruitment Genius: This is an opportunity for an I...

Day In a Page

Read Next
Larry Fink, the boss of fund manager BlackRock , is among those sounding the alarm  

Not all discounts are welcome: Beware the myopia of company bosses

Ben Chu
Cilla Black lived her life in front of the lens, whether on television or her earlier pop career  

Cilla Black death: A sad farewell to the singer who gave us a 'lorra, lorra laughs'

Gerard Gilbert
Turkey-Kurdish conflict: Obama's deal with Ankara is a betrayal of Syrian Kurds and may not even weaken Isis

US betrayal of old ally brings limited reward

Since the accord, the Turks have only waged war on Kurds while no US bomber has used Incirlik airbase, says Patrick Cockburn
VIPs gather for opening of second Suez Canal - but doubts linger over security

'A gift from Egypt to the rest of the world'

VIPs gather for opening of second Suez Canal - but is it really needed?
Jeremy Corbyn dresses abysmally. That's a great thing because it's genuine

Jeremy Corbyn dresses abysmally. That's a great thing because it's genuine

Fashion editor, Alexander Fury, applauds a man who clearly has more important things on his mind
The male menopause and intimations of mortality

Aches, pains and an inkling of mortality

So the male menopause is real, they say, but what would the Victorians, 'old' at 30, think of that, asks DJ Taylor
Man Booker Prize 2015: Anna Smaill - How can I possibly be on the list with these writers I have idolised?

'How can I possibly be on the list with these writers I have idolised?'

Man Booker Prize nominee Anna Smaill on the rise of Kiwi lit
Bettany Hughes interview: The historian on how Socrates would have solved Greece's problems

Bettany Hughes interview

The historian on how Socrates would have solved Greece's problems
Art of the state: Pyongyang propaganda posters to be exhibited in China

Art of the state

Pyongyang propaganda posters to be exhibited in China
Mildreds and Vanilla Black have given vegetarian food a makeover in new cookbooks

Vegetarian food gets a makeover

Long-time vegetarian Holly Williams tries to recreate some of the inventive recipes in Mildreds and Vanilla Black's new cookbooks
The haunting of Shirley Jackson: Was the gothic author's life really as bleak as her fiction?

The haunting of Shirley Jackson

Was the gothic author's life really as bleak as her fiction?
Bill Granger recipes: Heading off on holiday? Try out our chef's seaside-inspired dishes...

Bill Granger's seaside-inspired recipes

These dishes are so easy to make, our chef is almost embarrassed to call them recipes
Ashes 2015: Tourists are limp, leaderless and distinctly UnAustralian

Tourists are limp, leaderless and distinctly UnAustralian

A woefully out-of-form Michael Clarke embodies his team's fragile Ashes campaign, says Michael Calvin
Blairites be warned, this could be the moment Labour turns into Syriza

Andrew Grice: Inside Westminster

Blairites be warned, this could be the moment Labour turns into Syriza
HMS Victory: The mystery of Britain's worst naval disaster is finally solved - 271 years later

The mystery of Britain's worst naval disaster is finally solved - 271 years later

Exclusive: David Keys reveals the research that finally explains why HMS Victory went down with the loss of 1,100 lives
Survivors of the Nagasaki atomic bomb attack: Japan must not abandon its post-war pacifism

'I saw people so injured you couldn't tell if they were dead or alive'

Nagasaki survivors on why Japan must not abandon its post-war pacifism
Jon Stewart: The voice of Democrats who felt Obama had failed to deliver on his 'Yes We Can' slogan, and the voter he tried hardest to keep onside

The voter Obama tried hardest to keep onside

Outgoing The Daily Show host, Jon Stewart, became the voice of Democrats who felt the President had failed to deliver on his ‘Yes We Can’ slogan. Tim Walker charts the ups and downs of their 10-year relationship on screen