title: Spatial genetic structure of two HIV-I-resistant polymorphisms (CCR2-64 I and SDF1-3'A) alleles in population of Shandong Province, China.
abstract: OBJECTIVE
  To explore the spatial genetic structure of two HIV-I-resistant polymorphisms (CCR2-64 I and SDF1-3'A) alleles in the population of Shandong Province, China.
  
  
  METHODS
  Using the techniques of spatial stratified sampling and spatial statistics, the spatial genetic structure of the locus (CCR2-64 I and SDF1-3'A), which was shown to be important co-receptor for HIV infection, was quantified from the populations of 36 sampled counties of Shandong Province, and a total of 3147 and 3172 samples were taken for testing CCR2-64I and SDF1-3'A respectively from individuals without known history of HIV-I infection and AIDS symptoms.
  
  
  RESULTS
  There were significantly spatial genetic structures of the two alleles at different spatial distance classes on the scale of populations, but on the scale of individuals, no spatial structure was found in either the whole area of Shandong Province or the area of each sampled county. Although the change of frequencies of the two alleles with geographic locations in Shandong Province both showed gradual increase trends, their changing directions were inverse. The frequency of CCR2-64I allele gradually increased from the southwest to the northeast, while the frequency of SDF1-3'A allele gradually increased from the northeast to the southwest. However the RH to AIDS of combined types of their different genotypes did not represent obvious geographic diversity on the whole area of the Province.
  
  
  CONCLUSIONS
  The frequency of allele usually has some spatial genetic structures or spatial autocorrelation with different spatial distance classes, but the genotypes of individuals have random distribution in the same geographic area. Evaluating spatial distribution of the genetic susceptibility of HIV (AIDS) to CCR2-64I and SDF1-3'A alleles, should focus on the frequencies of combined genotypes of CCR2 and SDF1 based on the two-locus genotypes of each individual rather than the frequencies of CCR2-64I and SDF1-3'A alleles.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Shandong University, Jinan, China. xuefzh@sdu.edu.cn
authors.forename: Fu-Zhong
authors.initials: FZ
authors.lastname: Xue
authors.forename: Jie-Zhen
authors.initials: JZ
authors.lastname: Wang
authors.forename: Dao-Xin
authors.initials: DX
authors.lastname: Ma
authors.forename: Guo-Rong
authors.initials: GR
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Hu
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology / Q000235:genetics*; D054377:Chemokine CXCL12; D019743:Chemokines, CXC / Q000235:genetics*; D002681:China / Q000453:epidemiology; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D015497:HIV-1; D006801:Humans; D007113:Immunity, Innate / Q000235:genetics; D009154:Mutation; D011110:Polymorphism, Genetic; D054390:Receptors, CCR2; D019707:Receptors, Chemokine / Q000235:genetics*
chemical_list: C515334:CCR2 protein, human; C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; D019743:Chemokines, CXC; D054390:Receptors, CCR2; D019707:Receptors, Chemokine