Scientists in the UK have shown that genetic variations in the Y chromosome affect a male's risk of coronary heart disease. It is well known that males have a higher incidence of coronary heart disease than females due, in part, to the Y chromosome they inherit from their fathers. To investigate the role of the Y chromosome further, a team from the University of Leicester carried out research to determine whether genetic variations in the Y-chromosome affect risk for males.
Not all Y chromosomes are the same. There are variants within the male gender called "Y-haplogroups", which are usually associated with specific geographic regions and tend to indicate the origin of the ancestral line. Professor Nilesh Samani explains the background to the project that was funded by the British Heart Foundation, "We set out to determine if men with differing types of Y chromosome were at differing risk of heart disease. We tested nearly 3,000 British males, and found that those carrying the I-haplogroup variant had a 55 percent higher risk of coronary heart disease."
Of the 3,000 men tested, 1,295 were the cohort group of those with coronary heart disease and the rest were the control group. The Y-haplogroup was identified in all men, and the results showed that those in the I-haplogroup had an approximately 55 percent higher risk of coronary heart disease compared to the others. The association of the I-haplogroup with coronary heart disease was independent of, and not explained by, traditional heart risk factors such as cholesterol, high blood pressure and smoking.