Furthermore, a chi-square analysis showed significant differences in genotypes and allele frequencies for the CTNS gene SNP locus specific to the Polish Red breed, IGF2R gene SNP locus specific to the Polish HF breed, and the GHR and IQGAP2 genes SNP loci specific to the Hereford breed (S57 Table). The gene discussed is IQGAP2; the disease is hydrops fetalis.