Some physical traits that differ between sexes are known to be linked to certain single nucleotide polymorphisms (SNPs) outside the X and Y chromosomes. New research now suggests that many of these ‘sex-heterogenous’ SNPs also contribute to a person’s risk for a variety of diseases. Michela Traglia and colleagues at the University of California San Francisco presented their findings in PLOS Genetics.
Millions of SNPs are in each genome, with each SNP representing a difference in a certain DNA building block in a particular stretch of DNA. Many associations have been uncovered between certain SNPs and people’s distinct traits. Understanding SNPs has a number of applications, such as predicting individual treatment effectiveness or disease risks.
Traglia and colleagues previously found that SNPs associated with certain differences in physical traits between men and women, such as waist-hip ratio and basal metabolic rate, may also affect the biology of autism spectrum disorder and other complex diseases. Building on this work with two large genomic datasets, the identified an updated list of 2320 sex-heterogeneous SNPs.
Analysis of these SNPs revealed that they are also associated with a variety of health-related traits and diseases, some with strong sex bias and some without, including schizophrenia, type 2 diabetes, anorexia, heart failure, and ADHD.
These SNPs are located in stretches of DNA that are either within or near genes involved in skeletal and muscle development in a growing embryo. In addition, these SNPs appear to play a role in regulating gene expression and DNA methylation, which are fundamental processes by which a person’s DNA is translated into their distinct biology and traits.
Overall, the researchers conclude that the identified SNPs play a role in early-life biological processes shaping sex-distinct traits and which also affect health and disease risk later in life. More work is needed to understand the mechanisms behind these sex-heterogeneous SNPs.
“We found that genetic alleles with differing effects on measured physical traits in men and women also play an outsized role in health risks,” remarked study co-author Lauren Weiss. “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.”
Source: EurekAlert!
