Phenotypes

Tremors and astasia, as a consequence of hypoplasia of the forelimb-girdle muscles

Based on strong evidence obtained in Swiss Holsteins, Häfliger et al (2022) proposed KIR2DS1:p.Gln159* as the likely causal variant for haplotype HH13.

Sonstegard et al (2013) investigated the lethal Jersey haplotype, namely haplotype JH1 on chromosome BTA15 (see Mapping section). They first refined the haplotype "to a 15-marker window (15,162,470 to 15,949,175)" and then obtained whole-genome sequence from 11 bulls carrying this haplotype. Analysis of the sequence of these carriers in the candidate region revealed a "high-impact stop-gain SNP located at position 15,707,169 on BTA15. This C-t...

The double-muscle trait in cattle is characterised by an increase in muscle mass of approx 20%, resulting in substantially higher meat yield, a higher proportion of expensive cuts of meat, and lean and very tender meat, for which a substantial premium is paid. The trait is autosomal recessive, and the locus has been given the symbol mh. It occurs at such a high frequency in Piedmontese and Belgian Blue cattle that it is characteristic of these...

Syndactyly has been reported in many breeds of cattle in many countries. Most of the documentation, however, concerns its occurrence in US Holsteins, where, as a result of the siring of more than 60,000 calves by a bull who was subsequently shown to be a carrier, the disorder attracted considerable attention (Anon., 1967). The possibility that artificial selection favouring heterozygotes may have contributed to the unacceptably high frequency ...

"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)