SNP Identification in α2A-Adrenergic Receptor Gene in Chinese and the Effect on Gene Expression

Abstract：Objective: To scan single nucleotide polymorphism ( SNP ) in Chinese alpha-2A adrenergic receptor( α2A-AR )gene and study the effcts of the SNP on the gene expression .Methods: The complete sequence of α2A-AR gene was analyzed with autonated DNA sequencer to scan SNPs. Genomic DNA was extracted from whole blood and a 239 bp fragmnent containing the G/C polymorphism was amplified with PCR using a pair of specific primers.PCR-RFLP was used to perform the genotyping of the SNP at the site- 1 296 bp of the people in the North of China. Electrophoresis mobility shift assay( EMSA )was used to study the binding of the 390bp fragments(- 1 414-1 025 bp) with G or C at the site-1 296 bp and nuclear extracts. Results: In our study, two SNPs werefound in α2A-AR gene. Allele frequeneies of the SNP at the site- 1 296 bp were 0.61 and 0.39 for G and C, and the genotype frequencies were 0.34,0.54 and 0.13 for GG, GC and CC respectively from the people in the North of China.In the EMSA, a specific binding appeared in the complex of nuclear extracts and DNA with C at- 1 296 bp. Conclusion: Two SNPs exist in a2A-AR gene from the people in the North of China, and DNA fragment with allele C of the SNP at the site- 1 296 bp could bind with a specific protein, which could influence the gene expression.