| Figure 3: Marker-assisted backcross strategy
Microsatellite marker-assisted backcrossing allows for >99%
recipient genome content to be reached after five generations
(N5), thereby reducing the time frame for derivation of a
congenic strain to 12-14 months (“speed congenics”).
At backcross generations N2-N4, 10 mutation-carrying males
are subjected to full autosomal genome scans using 96 polymorphic
microsatellite markers. (Note that the X and Y chromosomes
become fixed without selection as a consequence of the breeding
scheme.) Two to three animals with the highest recipient genome
content are selected as breeders for the next generation.
At the N5 generation, males and females with near-100% recipient
genome content may be intercrossed to generate homozygous
congenics.
(Return to LASP Speed Congenics Services)
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