Key Insights – Lonn et al. 2017

Lonn, E., E. Koskela, T. Mappes, M. Mokkonen, A.M. Sims & P.C. Watts. 2017. Balancing selection maintains polymorphisms at neurogenetic loci in field experiments. Proceedings of the National Academy of Sciences, USA 114: 3690-3695.

OVERVIEW:
This paper characterized and experimentally manipulated the promoter microsatellite allele length for oxytocin receptor (Oxtr) and arginine vasopressin receptor 1a (Avpr1a) genetic loci. These allele lengths correspond to gene expression, and thus, provide variation for selection to act upon. The oxytocin and vasopressin neuropeptide systems are central mediators of socio-reproductive behaviors in mammals, and are anciently conserved among animals. This study demonstrated fitness effects of allelic variation in these loci, and how this variation is maintained.

NOVEL FINDINGS:
-this is the first study to characterize the promoter microsatellite for Oxtr.
-this is one of the first studies to identify sexually antagonistic (SA) genetic loci in vertebrates.
-this study links genotype to phenotype with corresponding fitness effects.

OTHER NOTABLE DETAILS:
-this study also innovated a new technique for artificial selection experiments by allowing the parental origin of each allele to be assessed. Through this technique, it was discovered that the alleles in females that survived and reproduced in the field differed from the alleles in males that survived and reproduced (i.e. sexual conflict).