Genetic basis of male testosterone levels

Scientists at the Metabolic Center of Greifswald, Institute of Clinical Chemistry and Laboratory Medicine have identified together with researchers from Europe and the USA, several gene variants that affect the male testosterone levels for life. As the American science journal "PLoS GENETICS" reports in its latest edition *, it managed to show the international scientific consortium that genetic factors are responsible for a decreased testosterone hormones concentration in blood.

Testosterone is the dominant sex hormone in men and plays a central role in the development of male sexual characteristics, the Muscle and bone metabolism.Between men of similar age, however, can observe significant differences in testosterone levels for which there is currently no conclusive explanation.

Scientists at the Metabolic Center of Greifswald, Institute of Clinical Chemistry and Laboratory Medicine and the Interfaculty Institute for Genetics and Functional Genomics jointly an international research consortium has formed to investigate the genetic regulation of male testosterone levels scientifically. Out of ten research institutes from seven countries are involved. Served as the basis of the study data and blood samples of the current study population Greifswald since 1997 "Health in Pomerania" SHIP (Study of Health in Pomerania) with more than 2,000 male subjects.

By evaluating the data collected from more than 14,000 men were able for the first time previously unknown genetic factors have been identified that have an influence on the regulation of male testosterone levels. The detected genetic effects on the hormone concentration in the blood could in future lead to a more differentiated diagnosis or medical treatment of testosterone hormone deficiency. "This is a significant advance to elucidate the causes of individual differences in male hormones testosterone levels and a further important step towards a personalized medicine," informed the Greifswald endocrinologist Prof. Dr. Henri Wallaschofski.



The scientists were able to demonstrate the Metabolic Center in accompanying analysis of 2,000 men of the SHIP study that low testosterone levels in the blood are often overweight, high blood pressure, lipid disorders and the development of type 2 diabetes are linked. "The identified genetic variants will help to understand the functional background of the shown associations between low testosterone hormone levels and cardiovascular risk factors better," said Dr. Robin Haring, co-senior author of the study and researcher at the University of Greifswald.

"The goal is to establish a diagnosis with individual risk assessment, lifestyle counseling and therapy and a scientific focus for metabolic diseases at the University Medical Center continues to expand," said Professor Matthias Nauck, Director of the Institute of Clinical Chemistry and Laboratory Medicine. The Individualized medicine is the central topic of research at the Medical University of Greifswald