Researchers based at the University of California, San Francisco (UCSF) have discovered DNA variants linked to physical differences between the sexes are associated with risks for various diseases such as autism spectrum disorder and heart failure.
It is known that the physiological differences between men and women can define the frequency and treatment outcomes of several diseases. However, in recent years the difference in genetics has also been found to be an important factor.
In this study, Michela Traglia, statistician at the UCSF Weill Institute of Neurosciences, and colleagues analyzed over 350,000 samples from men and women containing many genetic variants usually associated with sex-dependent physical traits from publicly available databases.
“We found that genetic alleles with differing effects on measured physical traits in men and women also play an outsized role in health risks,” said Lauren Weiss, a professor at UCSF Weill Institute of Neurosciences and senior of the study in a press statement.
The findings, published in PLOS Genetics, identified and confirmed a list of 2,320 single nucleotide polymorphisms that were different between men and women. They showed that DNA sites linked with female physical traits are linked to diseases such as heart failure while DNA regions linked to male traits are associated with health issues including bipolar disorder. Other diseases analyzed did not show any specific sex bias.
As well as the connection to disease, the authors also found sex-specific SNPs in DNA regions associated with embryonic development. This suggests a role in early-life biological processes that could affect the physical health of men and women differently at later stages in life.
Genetic differences between the sexes have previously been associated with different responses to medical treatments such as for glioblastoma, where female patients responded better to traditional treatment than males. Findings like these in combination with the underlying genetic concepts unveiled in the study by Traglia and colleagues, could have a variety of medical applications in disease diagnostics as well as allowing the development of more targeted treatment.
“We hope this work helps us to understand the genetic underpinnings of sexual dimorphism and its relationship with both early development and later disease risk,” adds Weiss.
The research by Traglia, Weiss and colleagues adds to an older study published in the same journal, where the team looked at genetic variants to determine sex bias in autism spectrum disorders. Here the researchers identified a prevalence of male trait associated SNPs in autism-related DNA regions.
“Deeper understanding of how sex differences arise and manifest in human health in general may eventually lead to insights into the biology of disorders with prominent sex differences,” Weiss told Inside Precision Medicine. However, the authors agree that further research will be needed to better understand the biological mechanisms causing sex-linked disease risks.