The Consequence of a Founder Effect: CCR5-∆32, CCR2-64I and SDF1-3'A Polymorphism in Vlach Gypsy Population in Hungary

Pathol Oncol Res. 2012 Apr;18(2):177-82. doi: 10.1007/s12253-011-9425-4. Epub 2011 Jun 11.

Abstract

Frequencies of genetic polymorphisms of the three most frequent HIV-1 resistance-conferring alleles playing an important role in HIV-1 pathogenesis were analysed in Vlach Gypsy populations living in Hungary, as the largest minority. Mutations in the encoding genes, such as CCR5-∆32, CCR2-64I and SDF1-3'A are shown to result in protective effects against HIV-1 infection and disease progression. 560 samples collected from Vlach Gypsy individuals living in 6 North-East Hungarian settlements were genotyped by PCR-RFLP method. Overall allele frequencies of CCR5-∆32, CCR2-64I and SDF1-3'A were found as 0.122, 0.186 and 0.115 respectively. All the observed genotype frequencies were in accordance with Hardy-Weinberg equilibrium . In regions, however, Vlach Gypsies live in majority and in ethnically homogenous communities, a higher CCR5-∆32 mutations were found, with allele frequencies of 0.148 and 0.140 respectively, which are remarkably higher than those in general Hungarian people, and ten times higher than in regions of North-Western India from where present day Hungarian Gypsies originated in the Middle Ages. In the background of this higher CCR5-∆32 allele frequency in the population analysed in our study a genetic founder effect could be assumed. Allele frequency of CCR2-64I was found to be among the highest in Europe. SDF1-3'A allele frequency in Vlach Gypsies was significantly lower than in ethnic Hungarians. 63% of the total 560 individuals tested carried at least one of the mutations studied. These results could partially explain the low incidence of HIV/AIDS among Vlach Gypsies in Hungary.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chemokine CXCL12 / genetics*
  • Disease Progression
  • Ethnic Groups / genetics
  • Europe / epidemiology
  • Founder Effect*
  • Gene Frequency
  • Genetic Predisposition to Disease
  • Genotype
  • HIV Infections / epidemiology*
  • HIV Infections / genetics
  • HIV Infections / virology
  • HIV-1 / genetics
  • HIV-1 / pathogenicity*
  • Humans
  • Hungary / epidemiology
  • India / epidemiology
  • Mutation / genetics
  • Polymerase Chain Reaction
  • Polymorphism, Genetic / genetics*
  • Polymorphism, Restriction Fragment Length
  • Receptors, CCR2 / genetics*
  • Receptors, CCR5 / genetics*
  • Roma / genetics*

Substances

  • CXCL12 protein, human
  • Chemokine CXCL12
  • Receptors, CCR2
  • Receptors, CCR5