DNA Variants Within the 5'-flanking Region of Milk-protein-encoding Genes II. The β-lactoglobulin-encoding Gene
Overview
Authors
Affiliations
For the detection of polymorphisms within the 5'-flanking region of the β-lactoglobulin (-LG) -encoding gene a nucleotide sequence containing 795 bp of the promoter and 59 bp of exon I was cloned and sequenced. After comparing the sequence from the DNA of 11 diverse cows (different breeds and milk-protein yields), 14 singlebp substitutions were identified within the 5'-flanking region and two in the 5'-untranslated region (5'-UTR) of exon I. Some of the variants are located in potential binding sites for trans-acting factors or in the 5'-UTR. A PCR-based RFLP analysis was performed, and the genotypes of an additional 60 cows were identified at five variable 5'-flanking sites. The results reveal three frequent combinations between the A and B alleles of the protein-coding region and the novel 5'-flanking DNA variants. This finding may explain the differences of the protein-variant-dependent β-LG synthesis (A>B) observed in vivo. A sequence comparison of the bovine and ovine promoters reveals an homology of 92.8% and shows a higher degree of conservation between positions -600 and -300.
Knutsen T, Olsen H, Ketto I, Sundsaasen K, Kohler A, Tafintseva V Genet Sel Evol. 2022; 54(1):35.
PMID: 35619070 PMC: 9137198. DOI: 10.1186/s12711-022-00731-9.
Unravelling genetic variation underlying de novo-synthesis of bovine milk fatty acids.
Knutsen T, Olsen H, Tafintseva V, Svendsen M, Kohler A, Kent M Sci Rep. 2018; 8(1):2179.
PMID: 29391528 PMC: 5794751. DOI: 10.1038/s41598-018-20476-0.
Schild T, Geldermann H Theor Appl Genet. 2013; 93(5-6):887-93.
PMID: 24162422 DOI: 10.1007/BF00224090.