SNP Identification in α_(2A)-Adrenergic Receptor Gene in Chinese and the Effect on Gene Expression

摘要

Objective: To scan single nucleotide polymorphism ( SNP ) in Chinese alpha-2A adrenergic receptor (α_(2A)-AR) gene and study the effects of the SNP on the gene expression. Methods: The complete sequence of α_(2A)-AR gene was analyzed with automated DNA sequencer to scan SNPs. Genomic DNA was extracted from whole blood and a 239 bp fragment 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 390 bp 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 were found in α_(2A)-AR gene. Allele frequencies 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 α_(2A)-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.