Presentations from the Symposium on Milk Genomics and Human Health

Opportunities for improving vitamin B12 content in bovine milk


Vitamin B12 plays an important role in human health. Macrocytic anemia and neurological disorder are well known symptoms of vitamin B12 deficiency. In addition, vitamin B12 may play a role in prevention of clinical entities as osteoporosis, neurocognitive decline, cardiovascular disease and neural tube defects in newborns. Dietary vitamin B12 is found only in animal products, and dairy is an important source of vitamin B12 in countries with a high dairy consumption. In addition, vitamin B12 from dairy is suggested to be better bioavailable than vitamin B12 from other sources. Therefore,... Read More... Download PDF

DNA methylation and ncRNA transcription at a CSN1S1 regulatory region in the bovine mammary gland

Objectives: Milk production in cows depends on all milk component synthesis and secretion by the mammary gland (protein, sugar, lipids…). This in turn involves a number of genes that are differentially expressed in this organ. In this study, we hypothesized that changes in gene expression profiles are related to differences in the methylation level at CpGs dinucleotides located within distal regulatory regions. As a first step, we focused on candidate regulatory regions of one casein gene (CSN1S1). Experimental methods: Holstein heifers were studied during early pregnancy (4 cows, day 60... Read More... Download PDF

Milk miRNA information and lactation

Micro-RNAs (miRNAs) are small RNA molecules known to participate in important regulatory mechanisms through the targeting of mRNAs by sequence specific interactions, leading to specific inhibition of gene expression. Initial studies highlight the importance of miRNA in normal development processes associated with the lactation cycle but a role in lactation is not yet completely clear. Recently, the identification of significant quantities of selective miRNAs in the milk of a number of mammals, together with the recent characterization of functional plant food miRNA in the blood of people,... Read More... Download PDF

The co-evolution of lactase persistence and dairying


Most Europeans take drinking milk for granted; it’s the everyday consumption of an everyday drink. But for most adult humans, indeed, for most adult mammals, milk is very far from an everyday drink. Milk is something that we have specifically evolved to be able to consume in the relatively recent past. The ability to digest the sugar in milk is called Lactase Persistence and Darwin’s engine of evolutionary change, natural selection, has probably worked harder on this trait than on any other biological characteristic of Europeans in the last 10,000 years. In this presentation we will see... Read More... Download PDF

Genetic parameters for fatty acids in Danish Holstein cattle based on SNP markers using a Bayesian approach


In recent years the interest for altering the fatty acid composition in bovine milk has been increasing. One possibility to do this is through selective breeding as the expression of some single fatty acids is influenced by the genetic composition. Variance estimates for fatty acids have been carried out in previous studies, but mainly on populations consisting of closely related individuals. Recent simulation studies have shown that variance estimates also can be obtained based on marker information, without information on relatives. The objective of this study was to estimate heritability... Read More... Download PDF

Genetic relation between composition of bovine milk fat in winter and summer

Substantial seasonal variation in milk fat composition has been found in European countries. The main cause for this seasonal variation seems to be the differences in diets: cows in Northern Europe are usually kept inside and fed silage in winter whereas in summer cows are mainly on pasture and fed with fresh grass. These differences in diets might affect the genetic background of milk fat composition and there are indications that nutrition affects mammary lipogenic gene expression. Because no information is available of possible genotype by season interaction on milk fat composition, the... Read More... Download PDF

Genetic and isoform variability in relation to milk coagulation properties

In the Danish-Swedish Milk Genomics initiative, genetic and isoform variation of the major bovine milk proteins have been characterized using several proteomic techniques (Jensen et al., 1212a, b, c). Among other, liquid chromatography-electrospray ionization/mass spectrometry (LC-ESI/MS) protein characterization revealed the presence of a variety of genetic variants of the major milk proteins, including αS1-casein (variants B and C), αS2-casein (A), β-casein (A1, A2, B, I, F), κ-casein (A, B and E), α-lactalbumin (B), and β-lactoglobulin (A, B, and C) in a milk subset selected to... Read More... Download PDF

Serial translocation via circular intermediates underlies color-sidedness in cattle

Colour sidedness is a dominantly inherited phenotype of cattle characterized by the polarization of pigmented sectors on the flanks, snout and ear tips. It is also referred to as 'lineback' or 'witrik' (which means white back), as colour-sided animals typically display a white band along their spine. Colour sidedness is documented at least since the Middle Ages and is presently segregating in several cattle breeds around the globe, including in Belgian blue and brown Swiss. We have demonstrated that colour sidedness is determined by a first allele on chromosome 29 (Cs(29)), which results from... Read More... Download PDF