Categories: Mortality / aging (incl. embryonic lethal)

Single-gene trait/disorder: yes

Mode of inheritance: Autosomal recessive lethal

Disease-related: yes

Key variant known: no

Cross-species summary: Phenes previously called ‘Abortion due to halplotype ….. ’ or ‘Abortion (embryonic lethality)’ , have been renamed to ‘Haplotype with homozygous deficiency, …’ or a phene name that is descriptive of the phenotype observed in homozygous affected animals [14/1/2022].

Species-specific symbol: BH1

Mapping: Using genotype data from tens of thousands of North American Holsteins, Jerseys and Brown Swiss cattle each genotyped with approximately 50K SNPs on the BovineSNP50 BeadChip, VanRaden et al. (2011) identified five new recessive lethal haplotypes by searching for common haplotypes that are never homozygous in live animals. One of these haplotypes occurs in Brown Swiss only, and (following a convention proposed by breed-association staff) VanRaden et al. (2011) named it BH1, where the B stands for Brown Swiss and the H for haplotype. The disorder described in this OMIA entry is BH1, which is located in chromosome BTA7, at 41-47Mb (UMD 3.0 genome assembly). Using a research strategy similar to that of VanRaden et al. (2011), Schwarzenbacher et al. (2012) confirmed the existence of BH1 in a sample of 2,959 Brown Swiss from Austria and Germany. (sourced from Cole et al. (2014), with thanks from FN) McClure et al. (2014) refined the mapping of haplotype BH1 on chromosome BTA7 to 42,811,272 to 47,002,161 (UMD3.1). Häfliger et al. (2021) identified the same haplotype in Brown Swiss cattle in their investigation of Brown Swiss and Original Braunvieh populations reared in Switzerland - see OMIA002513-9913 for more detail.

Molecular basis: In an extensive study involving exome capture and next-gen sequencing, McClure et al. (2014) were not able to discover any potentially causal variant for haplotype BH1.

Breed: Brown Swiss (Cattle) (VBO_0000166).
Breeds in which the phene has been documented. (If a likely causal variant has been documented for the phene, see the variant table breeds in which the variant has been reported).