Table 1. Behaviour and appearance in viewing jar.

Behaviour/Physical Trait	Criteria	Nfix +/+	Nfix +/−
Body position	Inactive	10%	16%
	Active	60%	44%
	Very Active	30%	40%
Tremor	Present	0%	0%
Palpebral closure	Present	100%	100%
Coat appearance	Normal	100%	100%
Whiskers	Present	96%	100%
Lacrimation	Present	100%	100%
Defecation	Present	40%	56%

Wild-type mice and Nfix ^+/− mice were placed in a large Perspex viewing jar (15 cm diameter) for approximately 2 minutes. Aspects of physical appearance and behaviour were scored during this time. No large differences were apparent between genotypes (Nfix ^+/+, n = 20; Nfix ^+/− n = 26).