Control and target gene selection for studies on UV-induced genotoxicity in whales

Table 5 Likelihood ratio tests showing the relation between gene expression and the presence of epidermal lesions

Gene	Expl	LRT	P
P53	oed:vac	1.78	0.62
	species	1.65	0.44
	vac	3.85	0.28
	oed	7.06	<0.01
	plate-random	5.03	0.02
HSP70	oed:vac	1.43	0.70
	vac	3.03	0.39
	oed	5.60	0.02
	species	19.60	0.0001
	plate-random	12.70	0.0004
KIN	oed:vac	1.65	0.65
	vac	3.21	0.36
	oed	0.79	0.37
	species	13.63	0.001
	plate-random	2.68	0.10

The explanatory variables included in the full model were ‘oedema’ (defined as a factor with two levels: absence = intercept, presence = oed), ‘vacuolation’ (vac, defined as a factor with four levels including absence=intercept) and the interaction between the two, ‘species’ (defined as a factor with 3 levels) was fitted as an explanatory variable to control for any potential effect on the variation of gene expression. ‘Plate’ was fitted as a random factor. Bold text indicates p ≤ 0.05. In all cases, the response variable transformed was: - log (ΔCt_gene).