Positional cloning using interval-specific congenic strains narrowed this QTL to a 0.44-Mb interval syntenic with human chromosome 1q23.2 (Kozell et al.
Because the DBA/2J and C57BL/6J mice that were used to generate the interval-specific congenic strains differ significantly in the brain levels of some oxidative stress markers (Rebrin et al.
(1) Congenic and interval-specific congenic strains refer to genetic animal models that are genetically identical to noncongenic (wild type) counterparts except for a limited genetic region (the congenic interval, which can range in size from moderately large to as small as 1 megabase).
KEY WORDS: Genetic theory of alcohol and other drug use; genetics and heredity; behavioral phenotypes, genetic trait, quantitative traits; quantitative trait locus (QTL), QTL mapping; congenics; interval-specific congenics (ISCs); congenic strains; animal models
Classical congenic strains typically are derived from two inbred progenitor strains (i.e., a donor strain and a recipient, or background, strain) that differ substantially in one or more behaviors of interest.
Traditional genetic analysis in the OLETF has been based on mapping QTL using microsatellite markers, followed by genetic isolation of QTL in congenic strains [8].
Matsumoto, "Fine mapping of the hyperglycemic and obesity QTL by congenic strains suggests multiple loci on rat chromosome 14," The Journal of Medical Investigation, vol.
In our previous study, we established two congenic strains in which limited segments of NSY-Chr14 were introgressed onto control C3H background genes [19].
Construction of new congenic strains will lead to fine mapping and identification of causal variants of the genes responsible for STZ susceptibility in the NSY mouse.
Estimates have been made of how much heterozygosity remains in
congenic strains, depending on the number of backcrosses used to produce them.
Using this strategy, one can produce several
congenic strains that carry different or overlapping parts of the original QTL.