Table 1.

Imputation scenarios with HD genotypes using different groups of purebred and crossbred animals

Scenarioa	Number of reference animalsb	Number of imputed animals	Description of reference animals	Density of reference panelc	Imputed group breedd	Density of panel of imputed animals
1_5K50K	500	116	Romney	50K	Romney	5K
1B_5KHD_1STEP	500	116	Romney	HD	Romney	5K
1B_5KHD_2STEP	17,000 + 500	116	Romney	HD	Romney	5K
2_50KHD	500	116	Romney	HD	Romney	50K
3_5K50K	469	116	Romney-31 animals related with the imputed group	50K	Romney	5K
3B_5KHD	469	116	Romney-31 animals related with the imputed group	HD	Romney	5K
4_50KHD	469	116	Romney-31 animals related with the imputed group	HD	Romney	50K
5_5K50K	500 (R) + 100 (P)	116	Romney + Perendale	50K	Romney	5K
5B_5KHD	500 (R) + 100 (P)	116	Romney + Perendale	HD	Romney	5K
6_50KHD	500 (R) + 100 (P)	116	Romney + Perendale	HD	Romney	50K

^aImputation scenarios were from 5K to 50K (50K was a subset of the HD panel), 5K to HD and 50K to HD

^b2-Step imputation: from 5K to 50K using all genotyped animals as reference population (N = 17,000) and from 50K imputed to HD using 500 animals as the reference population

^cThe oldest animals in each scenario were used as reference population

^dThe youngest animals in each scenario were imputed