Table 4.

Number of unique haplotypes observed and haplotype diversity (H_d) calculated within each breed, as well as defined based upon the presence/absence of the MSTN intron 1 SNP and SINE loci.

	Total haplotypes observed (2n)	Unique haplotypess	H d	SD
Within Breed
Belgian	56	11	0.799	0.031
Clydesdale	40	7	0.779	0.041
Florida Cracker	14	7	0.857	0.074
Mangalarga Paulista	30	14	0.784	0.078
Missouri Fox Trotter	42	19	0.916	0.025
Mongolian	40	26	0.971	0.013
Morgan	46	19	0.934	0.019
New Forest Pony	30	25	0.986	0.013
Puerto Rican Paso Fino	38	21	0.945	0.020
Quarter Horse	60	12	0.507	0.079
Shetland	40	14	0.885	0.027
Standardbred	66	11	0.666	0.061
Tennessee Walking Horse	38	10	0.826	0.037
Thoroughbred	62	9	0.680	0.040
All	602	100	0.954	0.003
Based upon MSTN variant
SINE	80	4	0.074	0.040
No SINE	522	96	0.960	0.003
C Allele	164	22	0.713	0.029
T Allele	438	78	0.953	0.004