Quantitative genetic study suggests sex-specific genetic architecture for fetal testosterone in a wild mammal

Abstract

Testosterone plays a critical role in mediating fitness-related traits in many species. Although it is highly responsive to environmental and social conditions, evidence from several species show a heritable component to its individual variation. Despite the known effects that in utero testosterone exposure have on adult fitness, the heritable component of individual testosterone variation in fetuses is mostly unexplored. Furthermore, testosterone has sex-differential effects on fetal development, i.e., a specific level may be beneficial for male fetuses but detrimental for females. The above mentioned may lead to a different genetic structure underlying the heritability of testosterone between the sexes. Here, we used a wild animal model, the feral nutria, quantified testosterone using hair-testing and estimated its heritability between parent and offspring from the same and opposite sex. We found that in utero accumulated hair testosterone levels were heritable between parents and offspring of the same sex. However, there was a low additive genetic covariance between the sexes, and a relatively low cross-sex genetic correlation, suggesting a potential for sex-dependent trait evolution, expressed early on, in utero.

Sex differences in the relationship between maternal and foetal glucocorticoids in a free-ranging large mammal

“…Liu et al, 2001), which is also referred to as foetal programming (Seckl & Holmes, 2007). There is increasing evidence, however, that there are sex differences in foetal programming (Braithwaite et al, 2018; Fishman et al, 2022; Liu et al, 2001). In mice ( Mus musculus ), for instance, higher maternal GC was associated with higher foetal GCs, but only in female offspring (Wieczorek et al, 2019).…”

“…In mice ( Mus musculus ), for instance, higher maternal GC was associated with higher foetal GCs, but only in female offspring (Wieczorek et al, 2019). In nutria ( Myocastor coypus ), in utero accumulated testosterone was found to be heritable, but only between parents and offspring of the same sex (Fishman et al, 2022). In birds, a meta-analysis found evidence that male offspring are typically more strongly affected by maternal steroid hormones in the egg than female offspring (Podmokła et al, 2018).…”

“…8), which is also referred to as foetal programming (Seckl & Holmes, 2007). There is increasing evidence, however, that there are sex differences in foetal programming (Braithwaite et al, 2018;Fishman et al, 2022;Liu et al, 2001).…”