Table 3. Body weight.

Behaviour/Physical Trait	Descriptive Term	Nfix +/+	Nfix +/−
Weight	Female (g)	21.37±0.782	21.46±0.782
	Male (g)	26.28±0.871	28.71±0.734

The weights (g) of wild-type mice and Nfix ^+/− mice were recorded. There was weak evidence (p = 0.08) to suggest that male Nfix^{+ /−} mice were on average heavier than male wild-type mice. There was no evidence that female Nfix ^+/− mice were heavier than female wild-type mice. The age that mice were weighed at varied from P63–P73. To account for this source of variation, ‘age-at-weigh-in’ was added as a covariate during the statistical analysis of these data (Nfix ^+/+, n = 20, 9 male, 11 female; Nfix ^+/−, n = 26, 12 male, 14 female).