Testing Evolutionary Theory With Modern Health Data
Though there have been successes in the battle against cardiovascular disease in recent decades, the fight has also gotten increasingly complicated. New treatments against established risk factors have failed trials, while brand new risk factors have emerged, leaving scientists scratching their heads and searching for better models of population health.
A study by Professor Mary Schooling of the Graduate School of Public Health and Health Policy and a colleague at the University of Hong Kong may give fresh perspective on this puzzle. In an article published in SSM – Population Health, the authors made a connection between big ideas and small-scale biology that could lead to new treatment or prevention strategies.
Evolutionary biology says that there is a trade-off between reproduction and living a long life. The theory maintains that an animal’s physical investments in fertility and procreation take energy away from maintenance of its own physiology. The scientists wondered if on a human level, then, there might be a connection between a reproductive hormone and heart disease. The hormone, gonadotropin-releasing hormone 1, or GnRH1, is the “central driver of reproduction,” the authors say, while ischemic heart disease (IHD) is the leading cause of death in the U.S. If the evolutionary theory held true, a reproductive driver like GnRH1 would increase the risk of a longevity reducer like IHD.
The researchers looked at the largest publicly available genetic study of IHD cases and control cases, and used genetic predictors to calculate how much GnRH1 each person would have had. Their work revealed that indeed, GnRH1 was positively associated with IHD. The good news is that scientists may be able to use this information to find new targets to fight IHD. For example, treatments that already target GnRH1, its effects, or its drivers, could potentially be repurposed for IHD.
“Showing a central tenet of evolutionary biology in humans is very exciting,” Schooling said in an interview with CUNY SPH, “more importantly it validates using well-established evolutionary theory to inform the prevention and treatment of chronic diseases.”