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Yes, polygenic sex determination is a thing!
Thomas D Kocher1, Richard P Meisel2, Tony Gamble3
1Department of Biology, University of Maryland, College Park, MD 20742, USA.
Trends in Genetics : TIG
|November 6, 2024
Summary
Polygenic sex determination (PSD) is more common than previously thought, with many animal species utilizing complex genetic and environmental interactions for sexual development. Misconceptions and experimental limitations may have historically underestimated its prevalence.
Area of Science:
- Developmental Biology
- Genetics
- Animal Reproduction
Background:
- Sexual development in animals is regulated by diverse mechanisms, including environmental cues and single 'master regulator' genes.
- Genetic factors, such as sex chromosomes, also play a role, with systems ranging from monofactorial to polygenic.
- The prevalence of polygenic systems in sex determination is often underestimated.
Purpose of the Study:
- To challenge the perception that polygenic sex determination (PSD) is rare in animals.
- To explore the potential biases and limitations contributing to the underestimation of PSD.
- To highlight the complex interplay of genetic and environmental factors in animal sexual development.
Main Methods:
- Review of existing literature on animal sexual development and sex determination mechanisms.
- Analysis of potential experimental and theoretical biases affecting the study of polygenic systems.
- Discussion of the continuum between monofactorial and polygenic sex determination systems.
Main Results:
- Many animal species likely utilize polygenic sex determination, involving multiple genes and environmental interactions.
- Experimental limitations, such as insufficient statistical power, may obscure the detection of multiple loci involved in PSD.
- Intellectual biases and misinterpretations of theoretical models may contribute to the underestimation of PSD.
Conclusions:
- Polygenic sex determination is a significant, yet potentially underappreciated, mechanism in animal sexual development.
- Further research with robust statistical power is needed to accurately assess the prevalence and mechanisms of PSD.
- Understanding PSD is crucial for a comprehensive view of animal reproductive biology and evolution.
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