Bos indicus introgression into (peri‐)alpine cattle breeds – evidence from the analysis of bovine whey protein variants

Summary The major bovine whey proteins, α ‐lactalbumin ( α‐ LA ) and β ‐lactoglobulin ( β ‐ LG ), exhibit breed‐specific genetic variation. The aim of this study was to identify possible new protein variants and determine the distribution of variants across a variety of 18 taurine and indicine cattle breeds applying a DNA ‐based sequencing approach. To this end, the open reading frames of the respective genes ( LALBA and LGB ) were sequenced in 476 animals. Within the LALBA gene, a previously unknown synonymous and a previously undesignated non‐synonymous nucleotide exchange were identified. Furthermore, two known α ‐ LA variants (A and B) and four known β ‐ LG variants ( A , B , C and W ) were determined. The occurrence of typical indicine variants in some taurine cattle breeds, such as S uisse E ringer, G erman H interwälder and H ungarian G rey S teppe, further supports the hypothesis of ancient B os indicus introgression into (peri‐)alpine cattle breeds.