|Kappes, Steven - Steve|
|Smith, Timothy - Tim|
Submitted to: Mammalian Genome
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/12/1997
Publication Date: N/A
Interpretive Summary: Muscular hypertrophy (mh) or "double muscling" is a naturally occurring syndrome in Belgian Blue cattle. The mh locus has been localized to a genetic interval of bovine Chromosome 2 (Chr) (BTA2), which is flanked by the centromere and a ms marker, TGLA44. We applied human comparative mapping information to the bovine map in order to identify a region of HSA2q that corresponds to the estimated location of mh, and use this information to extend coverage of the BTA2 map towards the centromere. Large genomic clones containing bovine homologues of seven genes located on the long arm of human Chr 2 (HSA2q) were isolated and physically mapped. Polymorphic markers developed from these clones were ordered on the BTA2 linkage map to more accurately determine the location and orientation of HSA2q conserved segments on the BTA2 comparative map. Our results extend map coverage towards the centromere and indicate that BTA2 contains at least five conserved segments of HSA2q. This analysis suggests the segment of human genome containing PROC corresponds to the region of BTA2 presumed to contain mh. Overall, our data reveals a complex rearrangement of gene order between bovine and human Chr2 that underscores the potential difficulty of applying comparative mapping information to identify genes underlying quantitative trait loci (QTL).
Technical Abstract: Muscular hypertrophy (mh) or "double muscling" is a naturally occurring syndrome in Belgian Blue cattle. The mh locus has been localized to an interval between the centromere and the microsatellite (ms) marker TGLA44 on bovine Chromosome 2 (Chr) (BTA2). We identified segments of conserved synteny that correspond to this region of BTA2 by assigning large genomic clones containing bovine homlogues of seven genes from the long arm of human Chr 2 (HSA2q). Polymorphic markers developed from these clones integrated the physical and linkage maps of BTA2 from 2q12 to 2q44 and extended genetic coverage towards the centromere. This comparative analysis suggests the mh locus resides on HSA2q between the protein C (PROC) and interleukin 1 receptor alpha (IL1RA) genes. Overall, our data reveals a complex rearrangement of gene order between BTA2q12-44 and HSA2q14-37 that underscores the need to establish boundaries of conserved synteny when applying comparative mapping information to identify genes underlying quantitative trait loci (QTL).