Abstract: To investigate the distribution of potential genetic polymorphisms in the promoter region of the protein phosphatase 2A-Aα subunit gene (PPP2R1A) in Guangdong Han population. METHODS: Genomic DNA samples were obtained from randomly selected healthy Cantonese subjects. Direct resequencing was applied to identify and to confirm the polymorphism sites in the 5'-flanking region of PPP2R1A. Allele frequencies of the potential genetic variants in the studied population were analyzed by HaploView Software and compared with HapMap data. RESULTS: 63 DNA samples (126 chromosomes) from the subjects (all Han Chinese) were completely re-sequenced with the PCR amplicons of target gene locus at (-1 844)-(+201) nt fraction. Six single nucleotide polymorphism (SNP) sites (with the MAF)，-1 039 G>T(+Ins) (rs10414793)(8.73%)，-568 G>A (rs1864007)(25.40%)，-241 -/G(rs11453459) (26.90%)， +87 T>C (rs13344984)(7.94%)，+107 -/C(rs3833207)(30.16%) and +108 A>G (rs17554825) (7.94%)，were confirmed. The frequencies of 2 polymorphism sites in our study were different from other foreign populations reported in HapMap data (P<0.05). Meanwhile，a noval potential SNP site，-512G>A(2.38%)，was identified in the current study. CONCLUSION: The PPP2R1A gene polymorphisms in 5' -flanking region and their allele frequencies were identified for the first time and reported in the general Guangdong Han population of Southern China. It provides the basis for further functional analysis of these polymorphism sites.

Key words: protein phosphatase 2A, scaffold Aα subunit, PPP2R1A gene, 5'-flanking region, polymorphism