Phenotypes

Häfliger et al. (2021) "characterize the phenotype and the genetic aetiology of a recessive form of congenital day-blindness observed in several cases of purebred Original Braunvieh cattle. ... Achromatopsia is a monogenic Mendelian disease characterized by the loss of cone photoreceptor function resulting in day-blindness, total color-blindness, and decreased central visual acuity."

By comparing whole-genome sequence of a small number of Holsteins having the trait, with sequence data from hundreds of control animals, Capitan et al. (2014) confirmed the mapping results of Lawlor et al. (2014) and identified the causal mutation as a de novo variant BTA3 g.C9479761T, which corresponds to a missense mutation p.R160C in the COPA gene that encodes coatomer protein complex, subunit alpha. By whole-genome sequencing of a Dominant...

The causative mutation for this disorder was discovered via the candidate gene approach. Tassi et al. (1984) reported a 10-15-fold decrease in the concentration of TG mRNA in affected cattle; Ricketts et al. (1985) reported the use of S1 nuclease assays and electron microscopy to narrow down the location of the mutation to the junction of exon 9 and intron 9; and Ricketts et al. (1987) reported the use of cloning and sequencing of genomic DNA ...

For eight of the nine haplotypes with a significant effect on calving rate (see Mapping section), Fritz et al. (2013) searched for causal mutations via whole-genome sequence data from 25 Holstein, 11 Montbéliarde and nine Normande bulls which had made major contributions to their breed. Specifically, they filtered "for mutations that were (a) located at+or –6 Mb from the detected haplotype (b) carried in the heterozygous state by the carrier b...

Häfliger et al. (2021) investigated “the two Braunvieh populations reared in Switzerland, the dairy Brown Swiss (BS) and the dual-purpose Original Braunvieh (OB). We performed a genome-wide analysis of array data of trios (sire, dam, and offspring) from the routine genomic selection to identify candidate regions showing missing homozygosity and phenotypic associations with five fertility, ten birth, and nine growth-related traits. In addition,...

Jacinto et al. (2022): "A trio whole-genome sequencing approach was carried out and identified a private homozygous missense variant in LAMB1 affecting a conserved residue (p.Arg668Cys)."

Murgiano et al. (2015) investigated a family of Pezzata Rossa cattle with 4 affected cows. The pedigree was suggestive of X-linked semi-dominant inheritance with lethality in hemizygous mutant males. Two autosomal segments on chromosome 7 and 14 also showed positive LOD scores in a linkage analysis and could not definitively be excluded. Whole genome sequencing of one affected cow at 28x coverage and comparison to the 1000 bull genomes' sequen...

Using targeted DNA capture and massively parallel resequencing of the 1.2 Mb region that contained 24 genes, Testoni et al. (2012) identified a causal mutation as a "KDM2B missense mutation (c.2503G>A) leading to an amino acid exchange (p.D835N) in an evolutionary strongly conserved domain". As the same authors report, "The KDM2B gene (also known as JHDM1B and FBXL10) encodes a histone H3 lysine 36 dimethyl (H3K36me2)-specific demethylase ....

Thomsen et al. (2010) showed that this disorder is due to a missense mutation (R560Q) at a site that is invariant from insects to mammals in the gene encoding spastin (SPAST or SPG4). In their table of reduced-fertility haplotypes, Cole et al. (2014) list this SPAST mutation as being the causal mutation for haplotype BHD.

Kromik et al. (2015; Genetics): c.196A>G; p.66Lys>Glu; NM_001192985.1