Identification of genetic signatures of positive selection in apes linked to life-history trait adaptations.

Abstract

Background: Apes, including humans, exhibit distinctive life history traits such as increased brain mass, delayed sexual maturity, and extended longevity compared to non-ape primates. These pronounced interspecific differences likely arise from underlying genetic architecture. However, the molecular mechanisms contributing to these traits remain largely unknown.

Objective: This study aims to identify genetic factors under positive selection that may have contributed to the evolution of ape-specific life history traits, particularly extended longevity.

Methods: Comparative genomic analyses were performed between 7 ape species and 22 non-ape primate taxa to identify positively selected genes (PSGs). Functional enrichment analyses were conducted to determine the biological processes associated with these PSGs. Additionally, expression analyses were carried out to assess tissue-specific patterns and their potential roles in neurodevelopment and systemic homeostasis.

Results: A total of 143 PSGs were idetntified, showing significant enrichment in biological processes including homeostatic regulation, protein complex assembly, and G protein-coupled receptor signaling pathways. Among these, ADCY5, PRKCB, and IL2 were of particular interest due to their established roles in longevity-associated mechanisms. Expression analyses revealed tissue-specific patterns suggesting potential involvement in brain evolution, neurodevelopment, and glucose homeostasis.

Conclusion: This study provides molecular insights into the genetic mechanisms underlying longevity in apes and highlights key biological processes that may have contributed to the evolution of ape-specific life history traits. These findings enhance our understanding of how positive selection has shaped complex phenotypes, particularly extended lifespan, in the ape lineage.