The genetic architecture of phenotypic diversity in the betta fish (Betta splendens)

Zhang, W.; Wang, H.; Brandt, D. Y. C.; Hu, B.; Sheng, J.; Wang, M.; Luo, H.; Guo, S.; Sheng, B.; Zeng, Q.; Peng, K.; Zhao, D.; Jian, S.; Wu, D.; Wang, J.; van Esch, J. H. M.; Shi, W.; Ren, J.; Nielsen, R.; Hong, Y.

doi:10.1101/2021.05.10.443352

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bioRxiv · 10.1101/2021.05.10.443352

The genetic architecture of phenotypic diversity in the betta fish (Betta splendens)

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Abstract

The Betta fish displays a remarkable variety of phenotypes selected during domestication. However, the genetic basis underlying these traits remain largely unexplored. Here, we report a high-quality genome assembly and re-sequencing of 727 individuals representing diverse morphologies of the betta fish. We show that current breeds have a complex domestication history with extensive introgression with wild species. Using GWAS, we identify the genetic basis of multiple traits, including several coloration phenotypes, sex-determination which we map to DMRT1, and the long-fin phenotype which maps to KCNJ15. We identify a polygenic signal related to aggression with many similarities to human psychiatric traits, involving genes such as CACNB2 and DISC1. Our study provides a resource for developing the Betta fish as a genetic model for morphology and behavior in vertebrates.

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Zhang, W., Wang, H., Brandt, D. Y. C., Hu, B., Sheng, J., Wang, M., Luo, H., Guo, S., Sheng, B., Zeng, Q., Peng, K., Zhao, D., Jian, S., Wu, D., Wang, J., van Esch, J. H. M., Shi, W., Ren, J., Nielsen, R., Hong, Y.. 2021-05-10. The genetic architecture of phenotypic diversity in the betta fish (Betta splendens). https://doi.org/10.1101/2021.05.10.443352

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