The variants identified in the resequencing and associated with idiopathic epilepsy are located in ADAM23. a. The 37 case-specific variants identified in Belgian Shepherds by targeted resequencing were located within a 39-kb region of ADAM23 and span exons 5–17 highlighted with blue. The entire ADAM23 region spanning 14,970,211–15,175,391 bp on CFA37 based on the UCSC Genome Browser on dog (CanFam3.1). Thirteen Illumina HD markers are within the ADAM23 gene, and four within the 39-kb region. There is a gap in the reference sequence in the 5’ end ADAM23, and the exon 1 sequence has high GC content. b. Association results of the 26 variants at the target region on CFA37 in Belgian Shepherds, Schipperkes, Finnish Spitzs, Beagles (Finnish hunting and German sub-populations), and combined data. The coding variants at 15113939 and 15113940 bp show inconsistent association between the breeds. c. There is strong linkage disequilibrium in the ADAM23 gene region in the four associated breeds: (i) Belgian Shepherds, (ii) Schipperkes, (iii) Finnish Spitzs and (iv) hunting Beagles from Finland. The most consistent association across breeds was identified for a six-variant risk haplotype spanning a 28-kb region containing exons 5–11 outlined with black