Prediction of heterosis from DNA fingerprints in chickens.

To assess the value of DNA fingerprints for the prediction of heterosis in chickens, retrospective analyses of data from three crossbreeding experiments and DNA fingerprints (DEP) of parental strains were conducted using two minisatellite and one middle-repetitive DNA probes. DEP bands were assessed on pooled DNA samples of 10-15 individuals per parental genetic group. The number of DEP bands evaluated in the experiments ranged from 81 to 139. The probes varied in their predictive value, but predictability of heterosis generally increased with multiple probes. Highly significant correlations (0.68-0.87) between band sharing ratios (SH) and heterosis were found in 25 crosses of White Leghorns in the first egg production cycle for age at sexual maturity, egg production, and mature body weight: traits with heterosis of 10% or more of the means. Regressions on SH explained 78.4% of the variation in heterosis in age at sexual maturity, 60.2% in egg production and 46.4% in mature body weight. For "broiler" traits with heterosis of < 1%, none of the correlations, based on 13 crosses, were significant. It was concluded that multilocus probe DFP of pooled DNA samples show promise as predictors of heterosis.