Fish as Model Systems to Study Epigenetic Drivers in Human Self-Domestication and Neurodevelopmental Cognitive Disorders

Abstract

Modern humans exhibit phenotypic traits and molecular events shared with other domesticates that are thought to be by-products of selection for reduced aggression. This is the human self-domestication hypothesis. As one of the first types of responses to a novel environment, epigenetic changes may have also facilitated early self-domestication in humans. Here, we argue that fish species, which have been recently domesticated, can provide model systems to study epigenetic drivers in human self-domestication. To test this, we used in silico approaches to compare genes with epigenetic changes in early domesticates of European sea bass with genes exhibiting methylation changes in anatomically modern humans (comparison 1), and neurodevelopmental cognitive disorders considered to exhibit abnormal self-domestication traits, i.e., schizophrenia, Williams syndrome, and autism spectrum disorders (comparison 2). Overlapping genes in comparison 1 were involved in processes like limb morphogenesis and phenotypes like abnormal jaw morphology and hypopigmentation. Overlapping genes in comparison 2 affected paralogue genes involved in processes such as neural crest differentiation and ectoderm differentiation. These findings pave the way for future studies using fish species as models to investigate epigenetic changes as drivers of human-self domestication and as triggers of cognitive disorders.

The enrichment of self-domestication and neural crest function loci in the heritability of neurodevelopmental disorders is not independent of genomic regulatory functions

“…Features of self-domestication have been found altered in people with ASD (Benitez-Burraco, et al 2016) and SCZ (Benitez-Burraco, et al 2017). Furthermore, loci implicated in mammal domestication appear to be dysregulated in the blood of individuals with ASD (Benitez-Burraco 2020), whereas genes exhibiting methylation changes in ASD and SZ are enriched in processes such as neural crest differentiation and ectoderm differentiation (Anastasiadi, et al 2022). Likewise, a previous study showed the polygenic component of psychiatric disorders and behavioral traits is associated with the phonological complexity of European languages in relation to local adaption (Polimanti, et al 2018), with types of languages being impacted, as noted, by changes in self-domestication levels (Benitez-Burraco and Progovac 2020).…”