oculocutaneous albinism in Braunvieh cattle

Cases of albinism have been reported in several species including cattle. Research so far has already identified many genes with an involvement in this eye-catching phenotype. Analysis of genotyping data (50k) of the two albinos, their mothers and eight five other relatives identified a 47.61-Mb candidate haplotype on BTA20. Subsequent comparisons of the albino sequence of this haplotype with sequence data of four Braunvieh sires and the Aurochs genome identified two possible candidate causal mutations at positions 39,829,806 bp (G/A; R45Q) and 39,864,148 bp (C/T; T444I) that were found to be absent in 1,682 animals from various bovine breeds from the 1000 bull genomes project. Both polymorphisms represent coding variants in the SLC45A2 gene, whose human equivalent harbors numerous variants associated with oculocutaneous albinism type 4.