title: The neck-region polymorphism of DC-SIGNR in peri-centenarian from Han Chinese population.
abstract: BACKGROUND
  DC-SIGNR (also called CD209L) has been extensively studied on its role in host genetic predisposition to viral infection. In particular, variable number tandem repeat (VNTR) of the neck-region of DC-SIGNR is highly polymorphic and the polymorphism has been investigated for genetic predisposition to various infectious diseases, though conflicting results had been reported. As infection is a major cause of human death and a mechanism of natural selection, we hypothesized that VNTR polymorphism of DC-SIGNR might have an effect on human life span.
  
  
  METHODS
  Here we collected 361 peri-centenarian individuals (age >or=94 for female and age >or=90 for male) and 342 geographically matched controls (age 22-53, mean 35.0 +/- 12.0) from Han Chinese. The VNTR polymorphism of the neck region was determined by PCR and genotype was called by separating the PCR products in agarose gel.
  
  
  RESULTS
  A total of 11 genotypes and 5 alleles were found in our population. The genotype distribution, allele frequencies and homozygote proportion did not show a significant difference between peri-centenarian and control group. As gender differences in lifespan are ubiquitously observed throughout the animal kingdom, we then stratified the samples by gender. There was more 6/7 genotypes in female peri-centenarian group than that in female control group, at a marginal level of significance (5.56 vs. 1.28%, p = 0.041). The difference was not significant after correction by Bonferroni method. It suggests a possible differential effect of DC-SIGNR VNTR genotypes between sexes. Further studies are warranted to confirm our preliminary findings and investigate the mechanisms of the underlying functions.
  
  
  CONCLUSIONS
  Our study indicated that there was absence of association between the neck region polymorphism of DC-SIGNR and longevity in Han Chinese population. But the question of whether the DC-SIGNR could affect longevity in a gender-specific pattern remains open.
authors.affiliation: State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, PR China. lihui19801019@gmail.com
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Cheng-Ye
authors.initials: CY
authors.lastname: Wang
authors.forename: Jia-Xin
authors.initials: JX
authors.lastname: Wang
authors.forename: Nelson Leung-Sang
authors.initials: NL
authors.lastname: Tang
authors.forename: Liang
authors.initials: L
authors.lastname: Xie
authors.forename: Yuan-Ying
authors.initials: YY
authors.lastname: Gong
authors.forename: Zhao
authors.initials: Z
authors.lastname: Yang
authors.forename: Liang-You
authors.initials: LY
authors.lastname: Xu
authors.forename: Qing-Peng
authors.initials: QP
authors.lastname: Kong
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: Zhang
mesh_terms: D000369:Aged, 80 and over; D000483:Alleles; D044466:Asian People; D015815:Cell Adhesion Molecules / Q000235:genetics*; D002681:China; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D037181:Lectins, C-Type / Q000235:genetics*; D008136:Longevity; D008297:Male; D018598:Minisatellite Repeats; D011110:Polymorphism, Genetic; D011956:Receptors, Cell Surface / Q000235:genetics*
chemical_list: C433029:CLEC4M protein, human; D015815:Cell Adhesion Molecules; D037181:Lectins, C-Type; D011956:Receptors, Cell Surface