Locus on chromosome 18 cosegregates with diabetes in the BB/OK rat subline.
The spontaneously diabetic BB rat is a well-established animal model of human insulin-dependent diabetes mellitus. Besides the lymphopenia gene (Iddm 1) and the MHC class-II genes of the RT1u haplotype (Iddm 2), at least one other non-MHC gene (Iddm 3) is considered essential for diabetes development. To investigate the participation of this third gene in the development of diabetes in our BB/OK rat subline, we analysed 119 [(BB/OK x DA)F1 x BB/OK] first backcross hybrids phenotypically and genotypically. Genotyping with 5 classical and 28 polymorphic microsatellite markers indicated that the third gene is located on chromosome 18, about 22 +/- 7 cM distal from the Olf locus (Iod score = 2.33). Significantly more diabetics than Iddm 1 and Iddm 2 homozygous nondiabetic subjects were homozygous for this locus. Interacting genes located on chromosomes X and/or 1 seem to be involved.
Klöting
I
I
Department of Laboratory Animal Science, Gerhardt Katsch Institute of Diabetes, University of Greifswald, Karlsburg, Germany.
Vogt
L
L
Serikawa
T
T
D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics*; D004195:Disease Models, Animal; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010641:Phenotype; D011110:Polymorphism, Genetic; D051381:Rats; D011913:Rats, Inbred BB