Carriers of this dominant gene have lower muscle pH, paler color, lower protein extractability, lower water-holding capacity, and greater cooking loss in the loin. On the positive side, carriers have a lower shear force value, a stronger taste and smell, and greater acidity. This defect is reported primarily in Hampshire or Hampshire-cross pigs and results from a single gene with two alleles that exhibit dominant-recessive inheritance. The dominant allele (RN-) is responsible for elevated glycogen stores in the muscle that results in increased production of lactate and subsequent reduction in ultimate pH upon slaughter. This results in lower quality meat and the so-called "acid meat" condition. The three genotypes currently can be classified by the estimation of glycolytic potential. The molecular basis has not yet been identified.