Phenotypes

Charlier et al. (2016): nonsense (stop-gain) p.Arg64∗

Agerholm et al. (2016): "a single base deletion in the first exon of CHRNB1 (c.55delG) introducing a premature stop codon (p.Ala19Profs47*) in the second exon, truncating 96 % of the protein."

Excluding variants found in breeds that do not show this trait, Daetwyler et al. (2014) narrowed the field down to "a missense mutation in KRT27 (c.276C>G; p.Asn92Lys; g.41636961C>G on BTA19; ss699911276)". Strong supporting evidence of the causality of this mutation was found by studying its presence in numerous bulls of the Montbeliarde breed (in which the trait occurs, and which, like Fleckvieh, derives from the Simmental breed) compa...

By cloning and sequencing a very likely comparative candidate gene (based on the homologous human disorder), Dennis et al. (2000) identified two causal mutations in Brahman cattle, namely a frameshifting 2-bp deletion (c.1057delTA; the "E7" mutation) and a nonsense mutation (c.1783C>T; p.Arg595Ter; the "E13" mutation) in the bovine GAA gene; and a 2-bp frameshifting deletion (c.2454delCA; the "E18" mutation) in Shorthorns.

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,...

Within the mapped candidate region (see Mapping section), Fritz et al. (2018) identified a likely causal variant as "an A-to-G transition at position 29,773,628 bp on chromosome 16 (g.29773628A>G; rs434666183)". The authors explained that "This A-to-G transition changes the initiator ATG (methionine) codon to ACG because the gene is transcribed on the reverse strand. . . . Initiation of translation at the closest in-frame Met codon would tr...

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,...

By comparing whole-genome sequenced data (from 2 affecteds and one control) in the candidate region (see Mapping section), and filtering resultant candidate variants, Duchesne et al. (2018) narrowed the field down to "a single substitution in exon 5 of KIF1C (chr19:27041449 C/T). For easier comprehension and since KIF1C gene in cattle is on the reverse strand, the substitution will be referred as KIF1C G>A in order to match with the transcr...

In what must be a sign of the times, Karageorgos et al. (2007) documented the first reported occurrence of this disorder in cattle and, in the same paper, also reported its molecular basis; in this case a missense mutation E452K (c.1354G>A) in the gene for alpha-N-acetylglucosaminidase (NAGLU).

Bourneuf et al. (2017): a de novo likely causal variant is COL1A1 p.1049_1050delinsS in Fleckvieh Petersen et al. (2019): "Whole-genome sequencing revealed the presence of a missense mutation in the alpha 1 chain of collagen Type I (COL1A1), for which both calves were heterozygous. The variant resulted in the substitution of a glycine residue with serine in the triple helical domain of the protein; in this region, glycine normally occupies eve...

Hiltpold et al. (2022) investigated a Brown Swiss bull with low semen quality: "The genome of this bull was sequenced at a 12× coverage to investigate a possible genetic cause. Comparing the sequence variant genotypes of this bull with those from 397 fertile bulls revealed a 1-bp deletion in the coding sequence of the QRICH2 gene which encodes the glutamine rich 2 protein, as a compelling candidate causal variant. This 1-bp deletion causes a f...

By cloning and sequencing a very likely comparative candidate gene (based on the homologous human disorder), Inaba et al. (1996) showed in a population of Japanese Black cattle, that this disorder is due to a nonsense mutation (CGA>TGA; Arg>Stop) in the gene for band 3 of red cell membrane, at the position corresponding to codon 646 of the human gene. The lack of this protein produces very unstable red-cell membranes, resulting in anaemi...

"Affected animals have a crooked tail and shortened head, growth retardation, extreme muscularity and spastic paresia, although some characteristics show variable penetrance. CTS is not lethal per se, but causes substantial economic losses due to growth retardation and treatment." (Charlier et al., 2008)