13 February 2012
ByAppeared in BioNews 644
A sixth of men have a genetic variant which could increase their risk of heart disease by up to 56 percent, according to a recent study.
The research, which looked at a subset of genes on the Y chromosome, which is only passed from father to son, might help to explain why men are at a higher risk for heart disease then women. The current lifetime risk for developing heart disease is one in two for men over 40, but only one in three for women in the same age group.
The team analysed 11 common genetic variants in the Y chromosomes of over 3,000 unrelated men, and used this to split them into subgroups. Men belonging to one of these groups, known as Haplotype I, were at a 56 percent higher risk for coronary artery disease (CAD) than men who did not inherit this haplotype.
This risk was independent of other factors, such as age, blood pressure, socioeconomic status, smoking or alcohol consumption.
'This gene variant is working through different mechanisms from the usual risk factors. It is difficult to say what the men affected can do about it because we don't yet understand its mechanism', said lead researcher Dr Maciej Tomaszewski, a senior clinical lecturer at the University of Leicester. 'The only advice we can give is to continue doing the good work in the department of lifestyle changes because that will reduce the risk of the known mechanisms'.
Further analysis revealed that some genes may be differentially expressed in those with haplotype I and other subgroups. While the exact role of these genes is unclear, some of them have been implicated in atherosclerosis.
The scientists conclude that it is too early to say that men should be tested for the gene, as more work is needed to decipher the complex interactions between the genes on the Y-chromosome, the immune system, and those already linked to increased risk of cardiovascular disease.Dr Hélène Wilson of the British Heart Foundation, which part-funded the work, told the BBC: 'Lifestyle choices such as poor diet and smoking are major causes, but inherited factors carried in DNA are also part of the picture. The next step is to identify specifically which genes are responsible and how they might increase heart attack risk'.