Muscle Gene Expression Associated with Increased Marbling in Beef Cattle

Abstract

Selection of breeding stock is a crucial step in any breeding program, therefore the methodology for animal evaluation has evolved rapidly and in recent decades has incorporated the use of molecular markers. Several multinational companies have made available to producers commercial tests based on these technologies, which allow assessing the predisposition of animals to express a specific phenotype. However, some doubts have begun to arise about negative effects of improper use of molecular markers, these are problems associated with inbreeding depression and long-term loss of response to selection. Therefore, the objective of this study was to assess allele and genotype frequencies of 4 polymorphisms associated with marbling in 7 beef cattle breeds being present in La Araucanía Region of Chile. We evaluated leptin, thyroglobulin, DGAT1 and FABP4 genes, which showed different frequency distributions among breeds with higher allele frequency for marbling in Aberdeen Angus breed and a low frequency in Belgian Blue and Hereford breeds. We conclude that it is feasible to use these tools in genetic programs, but it is also necessary to have reliable genealogical records and advice of professional or technical institutions that can integrate genotypic information from molecular markers in prediction models used for selection of breeding stock. Palabras clave: criterio de selección, marcadores moleculares, BLUP. INTRODUCCIÓN La selección de los reproductores de la siguiente gene-ración es un paso fundamental en todo programa de mejora genética. Para realizar esta selección, el mejorador debe utilizar el valor genético aditivo de los individuos, dejando para reposición aquellos animales cuya combinación de genes es la mejor para el carácter de interés. El objetivo de esta selección es maximizar la ganancia genética por generación mediante un correcto ordenamiento por mérito genético de los candidatos a ser reproductores (Buxade 1995). La genética ha dedicado un continuo esfuerzo a la obtención, a partir de la información fenotípica de un individuo y la de sus parientes, de un predictor del valor genético que se libere de los efectos ambientales y posea propiedades estadísticas óptimas (Buxade 1995). De esta manera, la metodología para la evaluación de los animales ha evolucionado rápidamente, y en las últimas décadas se ha pasado desde aquellas técnicas que consideraban tan solo parte de la información genealógica, mediante índices de selección (Smith 1936, Hazel 1943, Henderson 1990), a otras más sofisticadas que emplean toda la información (genealogía, sexo, raza, predio, variables productivas, etc.) mediante la metodología BLUP (Best Linear Unbiased Predictor) propuesta por Henderson (1949). De forma paralela, durante la segunda mitad del siglo XX los progresos realizados en biología molecular permitieron importantes avances en la identificación de las variaciones genéticas que se producen a nivel de la secuencia del ADN. La actividad ganadera no ha estado al margen de dichos avances y grandes multinacionales como P...

RNA-Seq Analysis Identifies Differentially Expressed Genes in Subcutaneous Adipose Tissue in Qaidaford Cattle, Cattle-Yak, and Angus Cattle

“…Hence, the relationship of NR2F2 expression with fat content in cattle needs further study and discussion. Studies have shown that MXRA8 expression level is associated with increased marbling in beef cattle [33]. In addition, LPIN1 is a candidate gene for fat deposition in pigs [34].…”

Molecular signatures of muscle growth and composition deciphered by the meta-analysis of age-related public transcriptomics data

“…However, to date a link between MXRA8 and lipid metabolism has been documented by only one publication. MXRA8 was indeed shown as an upregulated gene when bovines with high carcass adiposity and marbling were compared with slightly adipose bovines (16). The heat shock protein HSP 90-alpha (HSP90AA1) is related to muscular physiology by regulating transforming growth factor ␤ (TGF᎑␤), by folding the myosin motor domain and organizing the filament structure of myofibers (22).…”

Identification of single nucleotide polymorphisms in the ACADS gene and their relationships with economic traits in Hanwoo

“…Meat tenderness와 연관된 대표적인 유전자는 CAPN1(calciumactivated neutral protease 1)과 CAST(calpastatin) 등 이 있으며 (Casas et al, 2006;Morris et al, 2006;Nonneman et al, 1999;Oh et al, 2010;Schenkel et al, 2006), marbling score의 경우 DGAT1(diacylglycerol O-acyltransferase 1), TG(thyroglobulin) 그리고 LEP(leptin) Thaller et al, 2003) 상업적으로도 이용이 되고 있는 유 전자들이다. 이 외에도 육질형질과 관련된 많은 유전자들 이 보고되고 있으며 이를 활용한 육종 기술개발 연구가 진 행되고 있다 (Clark et al, 2011;Jiao et al, 2010;Lee et al, 2008;Marques et al, 2009;Wu et al, 2005).…”