In a study of mitochondrial DNA published in 2012, the Newfoundland pony and Canadian horse were found to be the most genetically diverse of the Canadian breeds studied, which also included the Sable Island horse and the Lac La Croix pony. When an estimation was made using microsatellite loci, the Newfoundland was found to have high autosomal diversity and a high number of haplotypes, some of which overlapped with the mountain and moorland pony breeds (historically documented as the ancestors of the Newfoundland), Nordic breeds and a feral population at Saint-Pierre et Miquelon. Overlapping haplotypes also suggested a relationship with the Standardbred and Clydesdale, suggesting possible crossbreeding at some point, although previous studies using microsatellite markers had not come to this conclusion. Although the microsatellite loci showed a relationship between the Newfoundland and the Sable Island horse, the study did not find overlapping haplotypes that would support this, possibly due to the population bottleneck in the 1980s that may have resulted in such haplotypes being lost. In order to be registered with the Newfoundland Pony Society, ponies must undergo DNA testing to verify Newfoundland parentage.