01943naa a2200241 a 450000100080000000500110000800800410001902400510006010000230011124501160013426000090025052012020025965000170146165000200147865000280149865300240152670000220155070000200157270000180159270000200161070000220163077300490165218815912022-08-10 2010 bl uuuu u00u1 u #d7 ahttps://doi.org/10.1080/104953909035046252DOI1 aSILVA, M. V. G. B. aCharacterization of DGAT1 Allelic effects in a sample of north american holstein cattle.h[electronic resource] c2010 aA putative causative mutation underlying a QTL was identified as a lysine to alanine non-conservative substitution at amino acid 232 of the gene encoding the acylCoA:diacylglycerol acyltransferase (DGAT1) protein. Our goal was to characterize the allelic substitution effects of this DGAT1 mutation in a large sample of Holstein bulls from North America. Statistically significant effects were identified for all of the milk production traits and somatic cell scores. Estimated average effects of substituting the lysine allele for the alanine variant on Holstein bull daughter yield deviations were −81 kg, 3.7 kg, −1.1 kg, 0.063%, 0.012%, and −0.023 units for milk yield, fat yield, protein yield, fat component, protein component, and SCS, respectively. These estimates were largely in agreement with previous studies; however, the magnitudes of the estimates were much smaller in this study. Impacts on economic indices for net merit, cheese merit, and fluid merit were modest. Because of the strong antagonism between fat and protein yield and how those traits influence economic indices, selection for DGAT1 genotypes will likely not find widespread application in the U.S. adairy cattle amilk production aquantitative trait loci aSubstitution effect1 aSONSTEGARD, T. S.1 aTHALLMAN, R. M.1 aCONNOR, E. E.1 aSCHNABEL, R. D.1 aTASSELL, C. P. V. tAnimal Biotechnologygv. 21, p. 88-99, 2010.