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Updated: Jul 15, 2026
10:07
Isolation of Giant Lampbrush Chromosomes from Living Oocytes of Frogs and Salamanders
Published on: December 5, 2016
Introgression in the genus Salmo via allotriploids
A G F Castillo1, E Beall, P Moran
1Departamento Biologia Funcional, Universidad de Oviedo, 33006 Oviedo, Spain.
Molecular Ecology
|April 4, 2007
Summary
Genetic introgression via allotriploids occurs between Atlantic salmon and brown trout. Despite this, parental species extinction is unlikely due to low allotriploid offspring survival.
Area of Science:
- Evolutionary biology
- Genetics
- Zoology
Background:
- Hybridization between sympatric species can lead to allotriploids.
- In animals, allotriploids are typically sterile, with rare nuclear DNA introgression.
- Reproductive modes in animal allotriploids include parthenogenesis, gynogenesis, and hybridogenesis.
Purpose of the Study:
- To investigate genetic introgression between Atlantic salmon and brown trout.
- To determine the role of spontaneous bisexual reproduction of allotriploids in gene flow.
- To assess the potential impact of introgression on parental species survival.
Main Methods:
- Utilized species-specific molecular markers.
- Analyzed genetic makeup of allotriploid offspring.
- Examined reproductive mechanisms in hybrid salmonids.
Main Results:
- Demonstrated genetic introgression between Atlantic salmon and brown trout.
- Identified spontaneous bisexual reproduction of allotriploids as a mechanism for introgression.
- Observed salmon-like offspring inheriting genes from brown trout.
- Documented very low survival rates for allotriploid offspring.
Conclusions:
- Allotriploids can facilitate nuclear DNA introgression between chromosomally distinct Salmo species.
- The low survival of allotriploid offspring suggests parental species extinction is improbable.
- This study highlights a rare instance of bisexual reproduction and introgression in animal allotriploids.
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