Genotyping of cows identified 1013 genes associated with udder morphology, mastitis, and production phenotypes (e.g., ESR1, FGF2, FGFR2, FGFR2, GLI2, IQGAP3, PGR, PRLR, RREB1, BTRC, and TGFBR2) [87]. This evidence concerns the gene PRLR and mastitis.