Phenotypes

As reported by Murgiano et al. (2014), the candidate region (mentioned in the Mapping section above) contains 42 annotated and several uncharacterised genes, none of which are obvious functional candidate genes for this disorder. Analysis of whole-genome sequencing data from of one of the affected calves (~x13.5) and 44 other cattle from 15 breeds narrowed the field of positional candidate causal mutations down to one SNV in an uncharacterised...

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)."

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 ....

Recognising the close resemblance of this disorder in Chianina cattle to Brody disease in humans, Drögemüller et al. (2008) illustrated the power of the candidate-gene approach by showing that this disorder in Chianina cattle is due to a missense mutation in the bovine version of the "Brody gene" - ATP2A1. Interestingly, another mutation in this same gene causes a far more severe set of clinical signs: congenital muscular dystonia 1 (OMIA 0014...

Jacinto et al. (2021) characterized "the pathological phenotype of a Romagnola stillborn calf with skeletal-cardio-enteric dysplasia and ... [identified] a genetic cause by whole-genome sequencing (WGS)."