title: Mapping of the bovine spinal muscular atrophy locus to Chromosome 24.
abstract: A hereditary form of spinal muscular atrophy (SMA) caused by an autosomal recessive gene has been reported for American Brown-Swiss cattle and in advanced backcrosses between American Brown-Swiss and many European brown cattle breeds. Bovine SMA (bovSMA) bears remarkable resemblance to the human SMA (SMA1). Affected homozygous calves also show progressive symmetric weakness and neurogenic atrophy of proximal muscles. The condition is characterized by severe muscle atrophy, quadriparesis, and sternal recumbency as result of neurogenic atrophy. We report on the localization of the gene causing bovSMA within a genomic interval between the microsatellite marker URB031 and the telomeric end of bovine Chromosome (Chr) 24 (BTA24). Linkage analysis of a complex pedigree of German Braunvieh cattle revealed a recombination fraction of 0.06 and a three-point lod score of 11.82. The results of linkage and haplotyping analysis enable a marker-assisted selection against bovSMA based on four microsatellite markers most telomeric on BTA24 to a moderate accuracy of 89-94%. So far, this region is not orthologous to any human chromosome segments responsible for twelve distinct disease phenotypes of autosomal neuropathies. Our results indicate the apoptosis-inhibiting protein BCL2 as the most promising positional candidate gene causing bovSMA. Our findings offer an attractive animal model for a better understanding of human forms of SMA and for a probable anti-apoptotic synergy of SMN-BCL2 aggregates in mammals.
authors.affiliation: Lehrstuhl für Tierzucht und Allgemeine Landwirtschaftslehre, Ludwig-Maximilians-Universität München, Veterinärstr. 13, D-80539 München, Germany. Ivica.Medjugorac@gen.vetmed.uni-muenchen.de
authors.forename: Ivica
authors.initials: I
authors.lastname: Medugorac
authors.forename: Juliane
authors.initials: J
authors.lastname: Kemter
authors.forename: Ingolf
authors.initials: I
authors.lastname: Russ
authors.forename: Detlef
authors.initials: D
authors.lastname: Pietrowski
authors.forename: Stefan
authors.initials: S
authors.lastname: Nüske
authors.forename: Horst-Dieter
authors.initials: HD
authors.lastname: Reichenbach
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schmahl
authors.forename: Martin
authors.initials: M
authors.lastname: Förster
mesh_terms: D000818:Animals; D002417:Cattle / Q000235:genetics*; D002874:Chromosome Mapping; D033481:Chromosomes, Mammalian / Q000235:genetics*; D006801:Humans; D008126:Lod Score; D018895:Microsatellite Repeats; D009134:Muscular Atrophy, Spinal / Q000235:genetics* / Q000662:veterinary*; D010375:Pedigree