East London genome project to track down beneficial genes
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Version 0 of 1. Scientists are planning to sequence the genes of 100,000 south Asian people in London, in an ambitious project to track down rare beneficial genes that protect against conditions from heart disease to cancer. The Pakistani and Bangladeshi communities in London have among the highest rates of poor health in Britain, with twice the average number of deaths from heart disease and five times the rate of type 2 diabetes. But within this population, scientists predict, there will be people who are unexpectedly healthy, whose genes could be conferring extreme resilience to disease. Powerful protective genes will be easier to track down in the Bangladeshi and Pakistani population, according to the scientists, due to the relatively high levels of cousin marriage in these groups. Having parents who are related makes it more likely that a person will carry two copies of a rare gene, rather than one, making the effects more pronounced. About 10% of people with Bangladeshi heritage have closely related parents and about 30-40% of those with a Pakistani background. The scientists hope that the study, called East London Genes and Health, will help break taboos of discussing cultural trends such as marriages between cousins. “This is not about telling people who to marry,” said David Van Heel, professor of genetics at Queen Mary University London, who is co-leading the project. “It’s about improving the health of the future generation.” In the quest to find beneficial versions of genes, scientists are particularly interested in so-called knockouts – mutations that block a gene from working completely. Knockout genes have been traditionally thought of as harmful, but there is growing evidence that it can sometimes help when a gene stops working altogether. Richard Trembath, professor of Medical Genetics, Queen Mary University of London, said: “You’ll see knockouts very rarely in the general population, but you’ll see them more often in populations with greater parental relatedness so there’s an opportunity for us to better understand them.” In the US, scientists recently discovered a knockout gene that causes carriers to have extremely low cholesterol and the findings have been used to successfully develop a cholesterol-lowering drug that blocks the same gene artificially. A study of the Finnish population found a knockout gene that protects against heart disease. “We know that there will be lots more genes like this, and some should show up in this study,” said Prof Trembath. The scientists are aiming to recruit 100,000 adult participants, through local GP surgeries, community meetings and mosques, who will answer an initial questionnaire and give DNA samples. About 1,000 participants will be recalled each year and invited to be involved in follow-up tests, such as blood analysis and MRI scans. People taking part will not be paid for the first stage of involvement, although their time will be compensated if they end up being recalled for secondary tests and chose to attend. The study will also provide a genetic baseline for what is “normal” in those of south Asian heritage and scientists hope that these findings could help explain why the population is more vulnerable to certain health problems. Pakistani men have the highest rate of heart disease in the UK and the risk of dying early from heart disease is twice as high among south Asian groups compared with the general population. People from south Asian communities are five times more likely to have type 2 diabetes. It is known that having related parents makes certain rare genetic disorders more likely, but the scientists said there was no evidence that it increases the risk of more common conditions such as high blood pressure or diabetes. “We don’t think that parental relatedness has any links with the health problems we’re studying,” said Van Heel. The findings could help provide more targeted and suitable treatment, he added, because until now the majority of genetics studies have focused on people of white, European descent. “Not only do south Asian people have some of the highest rates of poor health in the UK, they are also markedly under-represented in medical research and therefore not likely to benefit from the advances in genetics which are shaping the future of medicine,” he said. Anwar Ali Khan, a GP in the East End, said: “My hope is that through participating people will begin to have a greater awareness of their health.” |