An unusual British Heart Foundation (BHF) 'DNA database' from brothers and sisters across the UK has enabled researchers to pinpoint six genetic 'hotspots' that can double the risk of developing early heart disease.
By providing DNA samples, 2871 siblings from 930 families have taken part in the important genetic risk of acute coronary event (GRACE) study, aiming to find culprit genes that make some people more vulnerable to heart problems in middle age.
Researchers at University of Leeds analysed the samples for genetic differences between brothers or sisters with heart disease and those that are unaffected. They found that certain variations lead to more than a doubling of risk for some family members.
The results are being presented today to heart specialists at the European society of cardiology congress in Stockholm, Sweden.
The Congress will hear that the analysis of the GRACE collection has unearthed variations in three genes important in our natural defense to infections that seem to confer protection to heart disease, while another three – also part of our immune responses – seem to contribute to causing disease.
Whereas many studies compare disease sufferers to the general population, who will naturally have lots of genetic differences, the GRACE study was able to focus in on the important, hard-to-find, disease-causing variations because they were comparing siblings, who have very similar genetic make-up.
The research team led by Professor Alistair Hall found that although variations in individual genes increased the chance of heart disease, the cumulative effect of carrying lots of the 'bad' genes and fewer of the 'good' genes could double the risk.
Dr Ben Brown, who is presenting the study, said, "This is a really exciting finding. We are one of the first studies to examine such a large number of families affected by heart disease giving us real confidence in the results.
"We are starting to see how examining what we inherit from our parents and share with our brothers and sisters may put us at an increased risk.