MAP3K5 and hydrops fetalis: In addition, SNP hits in the IGF2R and MAP3K5 CG loci were highly polymorphic to the Polish Red breed, SNP hits in the INSIG1 and ATP6V1B2 CG loci were highly polymorphic to the Polish HF breed, and SNP hits in the PRLR, IGFBP2 CG loci were highly polymorphic to the Hereford breed.