Molecular cloning and mapping of the bovine and ovine skeletal muscle-specific calpains

The coding regions of the bovine and sheep skeletal muscle-specific calpain s (CANP3 or p94) were cloned and sequenced by RT-PCR. Direct sequencing con firmed open reading frames of 2466 bp for both species, and bovine and shee p CANP3 shared 98.5% identity in their amino acid code. These sequences wer e greater than 88% identical to human, pig, rat and mouse CANP3 nucleotide sequences, and greater than 93% identical for the amino acid code. Single n ucleo tide polymorphisms were used to map the bovine and sheep CANP3 genes in two steps. The genes were placed into linkage groups based on two-point LOD scores (greater than or equal to 3.0) and the best order was determined with multipoint linkage analysis (CRI-MAP vs. 2.4). Bovine CANP3 mapped to bovine chromosome 10, relative position 33.9 CM with linkage to nine marke rs; LOD scores ranged ham 4.89 to 8.61 (order, BMS2349-BL1035-RME25-CANP3-B M6305-BMS861-ILSTS053-BMS2742-CA090-BMS529). Ovine CANP3 mapped to chromoso me 7, relative position 58 CM, with linkage to only one marker, BMS861 (a b ovine microsatellite that has been used in sheep), with no recombination an d a LOD score of 5.72. The observed heterozygosity was 50% for both CANP3 m arkers in bovine and sheep pedigrees.