Whole Genome DNA Methylation Variations in Mammary Gland Tissues from Holstein Cattle Producing Milk with Various Fat and Protein Contents

Abstract

Milk fat and protein contents are among key elements of milk quality, and they are attracting more attention in response to consumers′ demand for high-quality dairy products. To investigate the potential regulatory roles of DNA methylation underlying milk component yield, whole genome bisulfite sequencing was employed to profile the global DNA methylation patterns of mammary gland tissues from 17 Canada Holstein cows with various milk fat and protein contents. A total of 706, 2420 and 1645 differentially methylated CpG sites (DMCs) were found between high vs. low milk fat (HMF vs. LMF), high vs. low milk protein (HMP vs. LMP), and high vs. low milk fat and protein (HMFP vs. LMFP) groups, respectively (q value < 0.1). Twenty-seven, 56 and 67 genes harboring DMCs in gene regions (denoted DMC genes) were identified for HMF vs. LMF, HMP vs. LMP and HMFP vs. LMFP, respectively. DMC genes from HMP vs. LMP and HMFP vs. LMFP comparisons were significantly overrepresented in GO terms related to aerobic electron transport chain and/or mitochondrial ATP (adenosine triphosphate) synthesis coupled electron transport. A total of 83 (HMF vs. LMF), 708 (HMP vs. LMP) and 408 (HMFP vs. LMFP) DMCs were co-located with 87, 147 and 158 quantitative trait loci (QTL) for milk component and yield traits, respectively. In conclusion, the identified methylation changes are potentially involved in the regulation of milk fat and protein yields, as well as the variation in reported co-located QTLs.

Comparison between indicine and taurine cattle DNA methylation reveals epigenetic variation associated to differences in morphological adaptive traits

“…Interestingly, LOC112444653, a 5.8S ribosomal RNA gene, showed the longest differentially methylated stretch (about 305 CpGs). LOC112444653 methylation has recently been reported to change in mammary gland tissue between cows producing milk with high and low fat and protein content [ 47 ]. This genomic region is involved in tissue formation and animal physiological characteristics.…”

Effects of DNA Methylation on Gene Expression and Phenotypic Traits in Cattle: A Review

“…In addition, correlation analysis identified 331 DMRs that were negatively correlated with the expression of differentially expressed genes (DEGs), 21 of which were located in the promoter region, which will provide a basis for marker-assisted selection in studies of meat quality traits [30]. Wang et al analyzed DNA methylation patterns in the breast tissues of 17 Canadian Holstein cows with different milk fat contents and found 706 differentially methylated CpG loci (DMCs) [131]. Among them, 83 DMCs and 87 quantitative trait loci (QTLs) were colocalized in milk composition and yield traits, indicating that these methylation changes potentially participate in the regulation of milk fat content [131].…”

“…Wang et al analyzed DNA methylation patterns in the breast tissues of 17 Canadian Holstein cows with different milk fat contents and found 706 differentially methylated CpG loci (DMCs) [131]. Among them, 83 DMCs and 87 quantitative trait loci (QTLs) were colocalized in milk composition and yield traits, indicating that these methylation changes potentially participate in the regulation of milk fat content [131].…”

Evaluación de la calidad composicional, sanitaria y microbiológica de la leche en el municipio de Sapuyes, departamento de Nariño, en el año 2021

“…Esta raza se caracteriza por una elevada producción de leche. Sin embargo, la selección genética ha tenido un impacto negativo sobre los sólidos totales, ya que es una raza con baja producción de estos parámetros, por lo que se busca mejorarlos 10 . Asimismo, hay otros parámetros que cambian la composición de la leche, entre estos se encuentra la alimentación, que es un factor que altera de manera más evidente la producción de grasa, lo que ha permitido mejorar su valor con el manejo nutricional.…”