Washington, May 9 : A new study has shown that it's not just diet or lifestyle that affect our health, by finding that genes also regulate levels of many blood proteins implicated in disease.

An international team of scientists from University of Exeter, the National Institute on Aging, and the Tuscany and Florence Health Agencies have shown how many of the key proteins within our blood are under genetic control.

The proteins include a class of molecules called "interleukins" that are important in inflammatory diseases such as multiple sclerosis and rheumatoid arthritis. They also play a crucial role in heart disease and related "metabolic" disorders.

For the study, the researchers studied a total of 42 circulating proteins.

The study showed variations in genes that influence "Sex hormone binding globulin," a protein that controls how much testosterone is freely available in one's blood.

The scientists also identified variations in genes that influence "Macrophage inflammatory protein beta" (MIP-beta), a protein that may play a role in influencing how likely people with HIV infection will go on to develop AIDS.

The identification of these genes could lead to a greater understanding of the diseases they are implicated in.

"By identifying versions of genes that alter blood levels of important molecules we should be able to understand whether these molecules are important in disease processes or not," said Professor Tim Frayling, one of the study's leaders.

The researchers believe that the findings would pave way for future studies focusing on how the whole genome influences all proteins, not just those that end up circulating in the blood, although these are some of the most important from a disease perspective.

The study is published in the open-access journal PLoS Genetics.