Q1Ucd1 affecting G26 was the least significant of any QTL identified in the original intercross and only reached a suggestive level of significance (LOD = 2.46, P < 0.05) [26]. In accordance, HG1 mice had small differences in all growth and length traits. NA in both sexes and 2WK, 3WK, 6WK and tail length in females was significant at a critical P < 0.005 (Table 4). The only difference in adiposity was a significant decrease in male MFP (Table 5). The successful capture and confirmation of the small effect Q1Ucd1-w26 QTL adds support to pursuing QTL identified at suggestive levels of statistical confidence from genome scans.