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Published on: April 26, 2017
Polygenic sex determination system in zebrafish
Woei Chang Liew1, Richard Bartfai, Zijie Lim
1Reproductive Genomics Group, Temasek Life Sciences Laboratory, Singapore, Singapore.
Plos One
|April 17, 2012
Summary
Zebrafish sex is genetically determined, not by environment, suggesting a polygenic system rather than chromosomal sex determination. Selective breeding can influence offspring sex ratios in this popular research model.
Area of Science:
- Genetics
- Developmental Biology
- Aquatic Model Organisms
Background:
- The sex determination (SD) mechanism in zebrafish, a widely used research model, remains largely unknown.
- Despite genomic resources, dimorphic sex chromosomes or primary sex-determining genes have not been identified.
- Environmental factors appear to have minimal influence on natural zebrafish sex ratios.
Purpose of the Study:
- To elucidate the genetic and environmental factors governing sex determination in zebrafish.
- To investigate the potential role of chromosomal sex determination (CSD) in zebrafish.
Main Methods:
- Classical breeding experiments and selective breeding for sex ratio bias.
- Genomic analysis using PCR-based assays and array comparative genomic hybridization.
Main Results:
- Significant variation in sex ratios among families was observed, with parental genotypes influencing offspring sex.
- Selective breeding demonstrated a genetic basis for sex ratio control.
- Genomic analyses did not reveal universal sex-linked differences between male and female zebrafish genomes.
- Evidence against a chromosomal sex determination (CSD) system was found.
Conclusions:
- Zebrafish sex is primarily genetically determined, with minor environmental influences.
- The absence of CSD and the genetic basis for sex ratio control suggest a polygenic sex determination system in zebrafish.
