SNP array data confirms genetic divergence of WKY strains. Multiple rat DNA samples from the WKY/NHsd, WKY/NCrl, and SHR/NCrl rats used in the behavioral studies were analyzed using a whole-genome Rat SNP array containing approximately 5,000 SNPs. The data were cleaned and displayed on cytogenetic maps of the rat genome. Blue = BB; Gray = AA; White = AB. Columns 1–2 WKY/NHsd-US; columns 3–4 WKY/NHsd-UK; columns 5–7 WKY/NCrl; column 8 SHR/NCrl. Note that all the WKY/NHsd rats appear isogenic, as do most of the WKY/NCrls, but they do not match each other or the SHR/NCrl completely.