| Calcium channels are composed of various subunits (α1,α2δ,βandγ) and those subunits have many sub-types respectively.α2δ1 subunit is main sub-type ofα2δsubunts in muscle calcium channels and codened by CACNA2D1 gene.The co-expression ofα2δ1 allows an enhancement in the membrane trafficking ofα1,associated with an increase in the number of ligand binding sites. In addition, co-expression of theα2δ1 subunit causes an increase in current amplitude, faster activation and inactivation kinetics in the voltage dependence of activation. As the second massager, calcium entry through voltage-gated calcium channels plays a key role in various physiological processes such as muscle contraction, hormone and neurotransmitter secretion, neuronal excitability, and gene expression.Mutations in many of muscle calcium channels can affect muscle calcium channelopathies such as Hypokalemic periodic paralysis, Muscular dysgeresis mice, Malignant hyperthermiae and Porcine stress syndrome.The evolution genetics analysis indicated that the usage of codon has mild bias in CACNA2D1 gene because all amino acids have its optima codon but on any amino acids using synonymous codon uniquely. The transitional pairs are more than transversional pairs among homology sequences. More transitions and transversion were found in 3rd codon positions than in 1st and 2nd codon positions. CACNA2D1 gene is much conserved. In the history of evolution, CACNA2D1 gene did not abide the theory of neutral mutation and undergo purifying selection.CACNA2D1 gene was located on 79.3～86.7 cM of porcine chromosome 9 by Radiation hybrid panel. Three QTL affecting ovulation rate, shoulder weight, body weight at 10 weeks of age respectively have been found in the located domain and one QTL affecting pH 24 hours post mortem has been found also near the area of CACNA2D1 gene mapped by integrative analysis of correlative databases. CACNA2D1 gene could be studied as a candidate gene influencing reproduction, carcass, growth traits, and meat quality traits of porcine.39106 bp genome DNA sequence of porcine CACNA2D1 gene (exon 8 to 3' UTR) including 32 exons,31 introns and 3'UTR partial sequence were amplified and sequenced.11965 bp of the 39106 bp genome DNA sequence were divided into 29 fragments and analysised by PCR-SSCP technology.82.1% exons and 76.9% coding nucleotides of porcine CACNA2D1 gene were analysised.21 SNPs were detected in 14 polymorphic fragments. E10-2, E1718, E35-2 and E38 are low polymorphic sits and the other 17 are medium polymorphic sits in the 21 SNPs. Primers E8 and E35 amplyfied fragment has three SNPs which build up three genotypes respectly. Primers E16 amplyfied fragment has three SNPs which build up four genotypes. Primers E10 amplyfied fragment has two SNPs which build up six genotypes. Primers E1718 and E38 amplyfied fragment has one SNPs which build up two genotypes respectly. Primers E14, E19, E26, E27, E3031, E37 and E39 amplyfied fragment has one SNP respectly and every one of these SNPs build up three genotypes.Association analysis of the 14 polymorphic fragments'genotypes with carcase and meat quality traits using the F2 generation of JianhuaxPietrain resource family was conducted by general linear model (GLM). In amplyfied fragment E8, pigs with genotype TG TC AG had more ham joint muscle weight than those with genotype GG CC GG by 0.336 kg and pigs with genotype TT TT AA had lower intramuscular fat content than those with genotype TG TC AG and GG CC GG respectly by 0.492% and 0.61% significantly (P<0.05); In amplyfied fragment E14, pigs with genotype GG had more area of loin muscle than those with genotype AG and AA by 3.306 and 5.625 cm2 respectly, pigs with genotype AG had heighter loin muscle and ham joint muscle pH45 value than those with genotype AA respectly by 0.24 and 0.211 significantly (P<0.05); In amplyfied fragment E16, pigs with genotype AT AG AA had lower h* value than those with genotype AA GG AT by 5.86, pigs with genotype AA GG AA had heighter lion muscle conductivity than those with genotype AT AG AA and AA GG AT respectly by 2.675 and 3.332 significantly (P<0.05); In amplyfied fragment E19, pigs with genotype TT had heighter ham joint muscle conductivity than those with genotype CC and CT respectly by 2.58 and 2.44 significantly (P<0.05); In amplyfied fragment E26, pigs with genotype TT had heighter intramuscular fat content than those with genotype CC and CT respectly by 1.943% and 1.786%, pigs with genotype CT had heighter intramuscular crude protein content than those with genotypes TT by 0.812% significantly (P<0.05); In amplyfied fragment E27, pigs with genotype GG had heighter intramuscular fat content than those with genotypes AA and AG respectly by 3.018% and 3.116%, pigs with genotype GG had lower intramuscular crude protein content than those with genotype AA and AG respectly by 1.056% and 0.984%, pigs with genotype AA had larger area of loin muscle than those with genotype AG by 4.06 cm2, pigs with genotype GG had lower content of water in muscle than those with genotype AA and AG respectly by 1.774% and 1.907% significantly (P<0.05); In amplyfied fragment E29, pigs with genotype AA had heighter ham joint weight than those with genotype AG by 0.486 kg, pigs with genotype AA had heighter ham joint fat weight than those with genotype AG and GG respectly by 0.36 kg and 0.292 kg, pigs with genotype AA had lower intramuscular crude protein content than those with genotype AG by 0.861% significantly (P<0.05); In amplyfied fragment E35, pigs with genotype CT GG CC had lower b* than those with genotype CT GG CT by 0.872, pigs with genotype CT GG CC had heighter h* than those with genotype CT GG CT by 5.359, pigs with genotype CT GG CC had lower ham joint muscle temperature than those with genotype CT GG CT and TT AG CT respectly by 2.651℃and 2.672℃significantly (P<0.05); In amplyfied fragment E37, pigs with genotype AA had lower intramuscular fat content than those with genotype AG by 0.929% significantly (P<0.05); In amplyfied fragment E38, pigs with genotype TT had heighter carcass weight than those with genotype CT by 1.04 kg significantly (P<0.05); In amplyfied fragment E39, pigs with genotype CC had lower ham joint muscle temperature than those with genotype AA and AC respectly by 2.461℃and 2.889℃significantly (P<0.05).
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