Background and Purpose: Rat chromosome 20 is one of special interest becaus
e it contains some diabetogenic genes, such as a major histocompatibility c
omplex (MHC)-linked genetic components and quantitative trait loci. We stud
ied rat chromosome 20, using the backcross progeny between BB/Wor and PVG.R
23 rats, and confirmed the genetic linkage map by use of another backcross
panel.
Methods: Backcross panels were done between BB/Wor and PVG.R23 rats, and BN
and KZC rats. Length variations of simple sequence length polymorphism mar
kers were analyzed by use of polymerase chain reaction (PCR) analysis. Alle
les of RT1-Bb and RT1-Db were analyzed by use of the PCR-restriction fragme
nt length polymorphism method. Genetic maps of rat chromosome 20 were const
ructed, using the Map Manager computer program.
Results: Fifty-two loci were mapped on rat chromosome 20, Genetic length wa
s 57.9 cM, with average spanning of 1.11 cM between markers. The positions
of RT1-N1, Tnf, and RT1-Bb into the MHC region were separated and confirmed
by results of two backcross panels in our linkage studies.
Conclusions: The genetic linkage map of rat chromosome 20 was improved, and
was a useful tool for genetic analysis of a diabetogenic gene(s) and for p
roducing MHC congenic strains.