Table S1. Metadata for 102 BCHF cases and their matched controls

Bovine congestive heart failure (BCHF) has become increasingly prevalent among feedlot cattle in the Western Great Plains of North America with up to 7% mortality in affected herds. BCHF is an untreatable complex condition involving pulmonary hypertension that culminates in right ventricular failure and death. Genes associated with BCHF in feedlot cattle have not been previously identified. Our aim was to search for genomic regions associated with this disease. A retrospective, matched case-control design with 102 clinical BCHF cases and their unaffected penmates was used in a genome-wide association study. Paired nominal data from approximately 560k filtered single nucleotide polymorphisms (SNPs) were analyzed with McNemar’s test. The most significant genome-wide association was in the arrestin domain-containing 3 protein gene (ARRDC3), followed by the nuclear factor IA gene (NFIA, mid-p-values, 1x10E-8 and 2x10E-7, respectively). Animals with homozygous risk alleles at either gene were approximately 8-fold more likely to have BCHF than their matched penmates without those risk alleles (CI95 = 3-17). Animals with homozygous risk alleles at both genes were 28-fold more likely to have BCHF than all others (p-value = 1x10E-7, CI95 = 4-206). A linked missense variant in ARRDC3 (C182Y) represents a potential functional variant since C182 is conserved among all other jawed vertebrate species observed. A DNA test with two markers showed 29% of 273 BCHF cases had homozygous risk alleles in both genes, compared to 2.5% in 198 similar unaffected feedlot cattle. This DNA test may be useful for identifying feedlot animals with the highest risk for BCHF in environments like those described here. Although pathogenic roles for ARRDC3 and NFIA variants associated with BCHF are unknown, their discovery facilitates classifying animals by genetic risk and allows cattle producers to make informed decisions for selective breeding and animal health management.