I.V. Petrescu-Mag, B. Păsărin, G. Hoha, Valerica Gîlcă, Ruxandra Mălina Petrescu-Mag
Abstract
In this paper we report on a special case of crossing-over in Poecilia reticulata. It was known fact that Snakeskin body trait (Ssb) can be both X-linked, or Y-linked, and also that the percent of recombination between Y and X chromosomes is 0.36, while reciprocal recombination, from X to Y, is 0.00; in other words, the gene was not known to recombine from X to Y. The aim of the current work was to present an accidental observation about the occurrence of crossing-over events from X chromosome to Y chromosome in our guppy broodstock. The results based on crossbreeding and progeny testing showed that Ssb recombination by crossing-over or gene conversion is possible both from X to Y and Y to X. These events have numerous evolutionary implications as long the color traits and behavior are very close interrelated in many animal taxa and not only in the guppy fish.
Key words: crossing-over, Poecilia, Snakeskin body, progeny test
