title: [Association study of MC1R gene polymorphisms with freckles in Chinese Han population from Chengdu].
abstract: OBJECTIVE
  To assess the association between single nucleotide polymorphisms (SNPs) of melanocortin-1 receptor gene (MC1R) and freckles in Chinese Han population from Chengdu.
  
  
  METHODS
  Twenty randomly selected samples were used to select SNPs of the MC1R gene through DNA sequencing. Pyrosequencing in combination with DNA pooling technique was used to assess allelic frequencies of the selected SNPs in 111 individuals with freckles and 124 normal controls. Representative SNPs were selected based on their functional implications and minimum allele frequency (MAF> 0.05). Genotype of the SNPs were determined with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) or pyrosequencing.
  
  
  RESULTS
  Based on results of DNA sequencing and pyrosequencing, 4 SNPs (rs2228479, rs885479, rs33932559 and rs2228478) were selected to determine the genotype for each sample. Comparison of genotypic and allelic frequencies of the 4 SNPs with χ (2) test has found no significant difference between the two groups (P> 0.05). For rs33932559, the frequencies of T allele were respectively 90.09% and 91.94% for individuals with freckles and normal controls. For rs2228479 and rs2228478, the frequencies of G and A allele were both about 77%. For rs885479, the frequency of T allele was about 60%. None of the above 3 SNPs showed a significant difference between the two groups in terms of allelic or genotypic frequencies.
  
  
  CONCLUSIONS
  No association between the selected SNPs of MC1R gene has been found with development of freckles for the selected Chinese Han population from Chengdu.
authors.affiliation: Department of Forensic Genetics, West China School of Basic Science and Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Liping
authors.initials: L
authors.lastname: Cao
authors.forename: Yi
authors.initials: Y
authors.lastname: Ye
authors.forename: Ruijuan
authors.initials: R
authors.lastname: Cong
authors.forename: Jin
authors.initials: J
authors.lastname: Wu
authors.forename: Yingbi
authors.initials: Y
authors.lastname: Li
authors.forename: Miao
authors.initials: M
authors.lastname: Liao
authors.forename: Jing
authors.initials: J
authors.lastname: Yan
mesh_terms: D000328:Adult; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D002681:China; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008548:Melanosis / Q000235:genetics*; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D044102:Receptor, Melanocortin, Type 1 / Q000235:genetics*; D055815:Young Adult
chemical_list: D044102:Receptor, Melanocortin, Type 1