The degree of lateralization of paw usage (handedness) in the mouse is defined by three major phenotypes

Abstract

Lateralization of paw usage in the laboratory mouse may be a useful model system in which to assess the genetic and developmental cause of asymmetry of hand usage. With a set number of paw reaches from a centrally placed food tube, individual mice from an inbred strain will exhibit a reliable number of left and right paw reaches. For a single inbred strain, there are approximately equal numbers of left-pawed and right-pawed mice, but strain differences have been reported in the degree of lateralization of paw preference. We reported a preliminary strain survey in which the strains appeared to fall into two groups of highly lateralized and weakly lateralized paw preference (Biddle et al., 1993). We review here our expanded survey of genetically different strains and stocks of the laboratory mouse, including different species and subspecies. The major genetic trait is the degree of lateralization of paw preference and the strain differences appear to fall into three major classes of highly lateralized, weakly lateralized, and ambilateral preference. The trait exhibits both additivity and dominance in preliminary reciprocal crosses, depending on which strain pairs are used. The wide difference between strains that have highly lateralized and ambilateral paw preference suggests specific genetic tools that could be used to begin a genetic dissection of the causes of this trait. Preliminary assessment of the size of the corpus callosum in three strains with significantly different degrees of lateralization suggests that genetically determined deficiencies and absence of this structure are not the direct cause of the strain differences in the trait of degree of lateralization. In the expanded survey, some strains appear to exhibit a directional deviation from equal numbers of mice with left and right paw usage. Therefore, direction of paw usage may not be a genetically neutral trait, but replicate assessments and genetic tests are needed to confirm this.

Handedness in the NAS/NRC Twin Study

“…This hypoth esis was m ade``more plausible by considering that the highly lateralized groups of strains may be similar to the HI and LO phenotype s that were selected by Collins' ' (Biddle & Eales, 1996, p. 392). But Biddle and Eales (1996) subsequently reported an expanded study of genetically different strains and stocks of the laboratory mouse, includ ing different species and subspecies. The m ajor genetic trait was degree of lateralisation of paw preference and the strain differences appeared to fall into three major classes of highly lateralised, weakly lateralised, and ambilateral preference.…”

Targeting the Full Length of the Motor End Plate Regions in the Mouse Forelimb Increases the Uptake of Fluoro-Gold into Corresponding Spinal Cord Motor Neurons

“…It is possible that this finding reflects forelimb use preference (i.e., handedness). Forelimb preference when reaching is well documented in the rat (Gharbawie et al, 2007; Alaverdashvili et al, 2008; Alaverdashvili and Whishaw, 2010; Morris et al, 2011); however, it is still a matter of debate in the mouse (Neveu et al, 1988; Takeda and Endo, 1993; Waters and Denenberg, 1994; Biddle and Eales, 1996; Bulman-Fleming et al, 1997). In the present study, forelimb use preference was not determined prior to the delivery of neuronal tracer.…”

Manual performance and laterality in twins of known chorion type

“…The degree of laterality has been studied extensively in animal models since the work of Collins (1985), who demonstrated that in mice it was under genetic control (see also Biddle et al, 1996). In a study on singleton siblings (Carlier et al, 1994), significant sibling resemblance for the performance of the preferred and nonpreferred hands in two manual tasks was observed.…”