Detecting parent of origin and dominant QTL in a two-generation commercial poultry pedigree using variance component methodology

Table 3 Highest test statistics and proportion of phenotypic variance explained at most likely QTL position when fitting additive QTL and dominance QTL effects for 40-day bodyweight and conformation score on chicken chromosomes 1, 4 and 5

Chr	pos	Model fitting additive QTL					Model fitting additive and dominant QTL
		^††LRT	^†variance component				^††LRT		^†variance component
		add	Va	Vp	Vc	res	addom	dom	Va	Vp	Vc	Vd	res
Bodyweight
1	55	5.0	0.07	0.09	0.02	0.89	5	0	0.07	0.01	0.02	0.00	0.89
4	85	5.0	0.04	0.04	0.03	0.89	5.7	0.6	0.03	0.05	0.02	0.02	0.88
5	5	1.4	0.02	0.06	0.02	0.89	5.3	3.9*	0.00	0.08	0.01	0.05	0.86
Conformation score
1	50	2.3	0.04	0.04	0.04	0.89	2.3	0	0.04	0.04	0.04	0.00	0.88
4	15	4.1	0.04	0.04	0.05	0.87	10.4*	6.3*	0.00	0.06	0.03	0.06	0.84
5	25	3.8	0.03	0.04	0.04	0.87	7.9*	8.1*	0.00	0.07	0.04	0.04	0.85

^†Proportion of phenotypic variance explained at highest test statistic (LRT) Vp: polygenic variance, Va: additive QTL variance, Vc: maternal (dam) variance, Vd: dominant QTL variance, res: residual variance
^††LRT is test statistic obtained from best position (pos), add is additive QTL versus null model, addom is additive and dominant QTL versus null model, dom is additive and dominant QTL versus additive QTL model * 5% linkage group-wise significance calculated from 1000 permutations of within dam genotype for 18 positions on chromosome 4 for weight and conformation-score

ISSN: 1297-9686