Genetic influences on behavior of infant Mus domesticus: a comparison of results from diallels derived from single and multiple populations.

A complete diallel cross was generated from six Jax inbred strains of Mus domesticus from diverse origins and a second 6 x 6 diallel generated from strains derived from a single wild population. During their second day of life, infants from both diallels were tested for latency to orient toward and root beneath mothers and, in a separate test, for latency to attach to mother's nipple. Rooting latency showed a significant additive maternal strain effect but little systematic effect of pup genotype. Nipple attachment latencies exhibited complete genetic dominance favoring rapid attachment, with no maternal effects. Patterns of genetic and influences obtained from the two diallels were highly similar for both behaviors, suggesting that for many traits the requirement that strains be drawn from a common base population may be relaxed.