TABLE 1

Analysis of WF.iddm4 N6 progeny

Progeny typenn (%) diabeticMean latency to diabetes (days)P*Number of diabetic rats with D4Arb9d allele
Congenic rats with BBDR-derived chromosome 4 alleles
 5103 (30)17<0.013/3
 6120 (0)NS0/0
 7127 (58)24<0.0017/7
 8187 (39)20<0.0017/7
 940 (0)NS0/0
 1052 (40)30<0.012/2
 11102 (20)30NS0/2
Congenic rats homozygous for WF-derived chromosome 4 alleles
 Pooled from progeny types 5–11533 (5)290/3
  • Data are the results of WF.iddm4 congenic progeny testing. N5 generation WF.iddm4 congenic rats with recombinant iddm4 intervals were identified and bred to WF.Art2a rats. Their N6 progeny were tested for susceptibility to the induction of diabetes as described in research design and methods. Seven subcongenic types were generated in this way. The approximate location and size of the BBDR rat-origin interval carried by each line is shown in Fig. 2.

  • * P values were calculated by 2 × 2 χ2 analysis. Indicated P values are with respect to the pooled group having all WF-derived chromosome 4 markers. Progeny of types 6, 9, and 11 could not inherit D4Arb9d alleles, which were not present in their N5 congenic parents. A fraction of the progeny from types 5, 7, 8, and 10 were recombinants that did not inherit D4Arb9d. The number of diabetic rats in each type of congenic that carried D4Arb9d is shown in the right-most column. NS, not significant.