Selection of discriminant SNP markers for breed andgeographic assignment of Italian sheep

With assignment methods are generally indicated several statistical approaches that usegenetic information to identify or verify membership of individuals or groups of individuals.In the present research, the stepwise discriminant analysis (SDA), the canonical discrimi-nant analysis (CDA) and the discriminant analysis (DA) were used to develop an assignmentmethod based on genotypes obtained from the Illumina’s OvineSNP50 BeadChip. The threestatistical techniques were used to select the most informative markers for discriminating21 different sheep populations (20 Italian and 1 Slovenian) and their 5 geographic areas oforigin. The procedure selected two reduced pools of markers, 110 and 108, that were ableto exactly discriminate the 5 geographic areas and the 21 sheep populations, respectively.Moreover, all animals were correctly allocated in the validation procedure. The obtainedresults indicated that the combined use of the SDA, CDA, and CD techniques represents anefficient strategy for selecting a reduced pool of highly discriminant markers. These SNPscould be further used to develop a low cost customized essay to trace the breed or thegeographic area of animals or derived foodstuffs.