Effects of breed and casein genetic variants on protein profile in milk from Swedish Red, Danish Holstein, and Danish Jersey cows.
In selecting cows for higher milk yields and milk quality, it is important to understand how these traits are affected by the bovine genome. The major milk proteins exhibit genetic polymorphism and these genetic variants can serve as markers for milk composition, milk production traits, and technological properties of milk. The aim of this study was to investigate the relationships between casein (CN) genetic variants and detailed protein composition in Swedish and Danish dairy milk. Milk and DNA samples were collected from approximately 400 individual cows each of 3 Scandinavian dairy breeds: Swedish Red (SR), Danish Holstein (DH), and Danish Jersey (DJ). The protein profile with relative concentrations of α-lactalbumin, β-lactoglobulin, and α(S1)-, α(S2)-, κ-, and β-CN was determined for each milk sample using capillary zone electrophoresis. The genetic variants of the α(S1)- (CSN1S1), β- (CSN2), and κ-CN (CSN3) genes for each cow were determined using TaqMan SNP genotyping assays (Applied Biosystems, Foster City, CA). Univariate statistical models were used to evaluate the effects of composite genetic variants, α(S1)-β-κ-CN, on the protein profile. The 3 studied Scandinavian breeds differed from each other regarding CN genotypes, with DH and SR having similar genotype frequencies, whereas the genotype frequencies in DJ differed from the other 2 breeds. The similarities in genotype frequencies of SR and DH and differences compared with DJ were also seen in milk production traits, gross milk composition, and protein profile. Frequencies of the most common composite α(S1)-β-κ-CN genotype BB/A(2)A(2)/AA were 30% in DH and 15% in SR, and cows that had this genotype gave milk with lower relative concentrations of κ- and β-CN and higher relative concentrations of αS-CN, than the majority of the other composite genotypes in SR and DH. The effect of composite genotypes on relative concentrations of the milk proteins was not as pronounced in DJ. The present work suggests that a higher frequency of BB/A(1)A(2)/AB, together with a decrease in BB/A(2)A(2)/AA, could have positive effects on DH and SR milk regarding, for example, the processing of cheese.
Department of Food Technology, Engineering and Nutrition, Lund University, PO Box 124, SE-221 00 Lund, Sweden. Electronic address: Frida.Gustavsson@food.lth.se.
F
F
Gustavsson
Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
A J
AJ
Buitenhuis
Department of Food Science, BioCenter, Swedish University of Agricultural Sciences, PO Box 7051, SE-750 07 Uppsala, Sweden.
M
M
Johansson
Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
H P
HP
Bertelsen
Department of Food Technology, Engineering and Nutrition, Lund University, PO Box 124, SE-221 00 Lund, Sweden.
M
M
Glantz
Department of Food Science, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
N A
NA
Poulsen
Department of Food Technology, Engineering and Nutrition, Lund University, PO Box 124, SE-221 00 Lund, Sweden; LRF Dairy Sweden, Ideon Science Park, SE-223 70 Lund, Sweden.
H
H
Lindmark Månsson
VikingGenetics, PO Box 64, SE-532 21 Skara, Sweden.
H
H
Stålhammar
Department of Food Science, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
L B
LB
Larsen
Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, PO Box 50, DK-8830 Tjele, Denmark.
C
C
Bendixen
Department of Food Technology, Engineering and Nutrition, Lund University, PO Box 124, SE-221 00 Lund, Sweden.
M
M
Paulsson
Department of Food Science, BioCenter, Swedish University of Agricultural Sciences, PO Box 7051, SE-750 07 Uppsala, Sweden.
A
A
Andrén
D000818:Animals; D002364:Caseins / Q000235:genetics* / Q000378:metabolism; D002417:Cattle / Q000235:genetics* / Q000378:metabolism; D003718:Denmark; D005260:Female; D005838:Genotype; D007768:Lactalbumin / Q000235:genetics; D007782:Lactoglobulins / Q000235:genetics / Q000378:metabolism; D008892:Milk / Q000737:chemistry*; D008894:Milk Proteins / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D011110:Polymorphism, Genetic; D013045:Species Specificity; D013548:Sweden
D002364:Caseins; D007782:Lactoglobulins; D008894:Milk Proteins; D007768:Lactalbumin
casein; composite genotype; genetic polymorphism; milk protein composition