Abstract
Data from chromosomal in situ hybridization and restriction fragment length polymorphism (RFLP) of ribosomal DNA (rDNA) obtained from the same individuals of two subspecies of the Australian grasshopper Caledia captiva, suggest the occurrence of biased exchange of DNA sequences in hybrid individuals. Thus, there are a disproportionate number of Torresian individuals that possess Moreton ribosomal RNA gene sequences. This bias correlates with the previously described pattern of asymmetrical introgression of Moreton rDNA into Torresian populations. The present findings demonstrate the potential effect of biased gene conversion on the frequencies of introduced gene variants.
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Arnold, M.L., Contreras, N. & Shaw, D.D. Biased gene conversion and asymmetrical introgression between subspecies. Chromosoma 96, 368–371 (1988). https://doi.org/10.1007/BF00330703
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DOI: https://doi.org/10.1007/BF00330703