A gene-imposed nervous system difference influencing behavioral covariance.

Behavioral and physiological scores from 697 mice sampled from lines at various times during their response to bidirectional selection for divergent caudal nerve conduction velocity suggest broad-reaching behavioral effects of the gene differences among lines. Sciatic nerve conduction velocity differences as well as line differences in reflexive leg withdrawal indicate gene effects general to other peripheral nerves and to behaviors with known dependence on functional by those nerves. Independently replicated line differences for open-field activity and defecation demonstrate effects on more complex behaviors with no obvious direct relationship to peripheral nerve conduction velocity. The direction of line differences in open-field behaviors suggests that genetic variance for peripheral nerve function may contribute to genetic covariance between these behaviors.