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Title: Many functionally connected loci foster adaptive diversification along a neotropical hybrid zone
Characterizing the genetic complexity of adaptation and trait evolution is a major emphasis of evolutionary biology and genetics. Incongruent findings from genetic studies have resulted in conceptual models ranging from a few large-effect loci to massively polygenic architectures. Here, we combine chromatin immunoprecipitation sequencing, Hi-C, RNA sequencing, and 40 whole-genome sequences from Heliconius butterflies to show that red color pattern diversification occurred via many genomic loci. We find that the red wing pattern master regulatory transcription factor Optix binds dozens of loci also under selection, which frequently form three-dimensional adaptive hubs with selection acting on multiple physically interacting genes. Many Optix-bound genes under selection are tied to pigmentation and wing development, and these loci collectively maintain separation between adaptive red color pattern phenotypes in natural populations. We propose a model of trait evolution where functional connections between loci may resolve much of the disparity between large-effect and polygenic evolutionary models.  more » « less
Award ID(s):
1656514 1736026 1656389
NSF-PAR ID:
10218813
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
39
ISSN:
2375-2548
Page Range / eLocation ID:
eabb8617
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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