TABLE 3.

Single- and multiple-regression results for selected traits with multiple QTL

	SNP	Chromosome	Position (bp)	Significance	Single R2	Multiple R2
WT	gnl.ti.390449323_1	7	46,696,633	**	0.34
	BICFPJ1156983	9	46,401,136	**	0.10
	BICF232J28587	10	7,033,361	NS	0.19
	gnl.ti.360206886_2	10	11,465,975	**	0.12
	gnl.ti.351411336_1	15	37,006,665	***	0.14
	BICFPJ263341	15	44,228,026	***	0.48
	BICFPJ1062878	34	21,414,695	**	0.20
					Σ = 1.6 (1.4)	0.69
Snout rat	gnl.ti.355951851_2	1	97,045,173	***	0.15
	BICF229J36361	9	50,982,910	**	0.11
	BICF236J54123	12	57,797,364	**	0.11
	gnl.ti.390310078_3	21	27,755,937	**	0.15
	BICF229J63639	32	32,959,130	***	0.24
					Σ = 0.8	0.44
HT	gnl.ti.390449323_1	7	46,696,633	***	0.35
	BICF232J28587	10	7,033,361	NS	0.17
	gnl.ti.360206886_2	10	11,465,975	***	0.16
	BICFPJ263341	15	44,228,026	***	0.53
	BICFPJ1062878	34	21,414,695	**	0.19
					Σ = 1.4 (1.2)	0.65
head.rat	BICF229J19878	9	25,422,459	NS	0.08
	gnl.ti.350815589_1	22	10,294,335	***	0.13
	BICFPJ1062878	34	21,414,695	***	0.15
	gnl.ti.390146013_1	38	24,931,616	***	0.13
					Σ = 0.5 (0.4)	0.34

Trait, SNP, SNP chromosome location, and SNP base-pair position on the chromosome are indicated in the first four columns. Significance is noted as not significant (NS); (*) 0.01 < P < 0.05; (**) 0.001 < P < 0.01; (***) P < 0.001. “Single R²” presents the amount of variation explained by a single SNP in the single-regression model. “Multiple R²” presents the amount of variation explained with all SNPs in the same model. The sum of SNP single R² is presented in two forms: the total sum (Σ) or the total minus the R² of values that were not significant. Some traits were transformed to achieve a better fit to the normal distribution: Snout.rat was squared. Height was arcsine square root transformed; head.rat was log transformed.