Genetic factors on the male sex Y chromosome may in part explain the greater susceptibility of men to coronary heart disease, according to a British-Australian study presented at the European Society of Cardiology Congress in Stockholm.
Coronary heart disease (as well as deaths from it) is much more common among men than among women of the same age group, said Nilesh J. Samani of the University of Leicester, contributor to the study at a press conference.
It can be suspected that this is due to both the different lifestyle of men, e.g. more frequent smoking, and hormones. But one of the potential causes of these differences may be genetic factors located on the male sex Y chromosome, which is not present in women, the specialist explained.
To test this hypothesis, British scientists together with colleagues from Australia conducted genetic tests among nearly 3. biologically unrelated men from Great Britain, of whom 1295 suffered from coronary heart disease. The differences in the DNA sequence of the Y chromosome, referred to as male-specific – MSY, were analyzed. They are inherited from father to son and are usually related to specific geographic regions, and therefore allow to determine where the ancestors of a given man came from.
On the basis of the differences found (so-called polymorphisms), the examined men were assigned to 12 different lines, the so-called haplotypes.
It found that those who belonged to haplotype 1 were 55 percent. more likely to develop coronary heart disease than men from other lines.
This was not related to other known risk factors for this condition, such as age, high blood pressure, smoking, and levels of good (LDL) and bad (HDL) cholesterol.
Our research has shown that genetic variations in the Y chromosome may have an impact on the risk of coronary heart disease and in part may also explain the greater predisposition of men to the disease, Samani said.
Haplotype 1 is most widespread in northern, central and eastern Europe, especially in Sweden, Norway and northern Germany, where it is found in more than 60 percent. men in the population. However, it is much less common in southern Europe. Hence, researchers are wondering if these differences might correspond to a higher rate of coronary heart disease among northern Europeans.
In Poland, the highest percentage of men with this haplotype live in the northwest of the country.
Joanna Morga (PAP) from Stockholm