CCR2 Genetic Polymorphism And Its Potential Effect On HIV Acquisition In A Population Of Children Living In The Northern Region Of Cameroon.

BACKGROUND AND OBJECTIVES: The association of chemokine receptor-2 (CCR2) polymorphism with HIV transmission or disease progression remains highly controversial. The role of CCR2-64I allele in HIV infection may differ from one population to another because of their genetic background. The objectives of this study were to characterize the CCR2 genetic polymorphism and to determine its potential effect in HIV acquisition in children living in the Northern Region of Cameroon. MATERIALS AND METHODS: A cross-sectional study was carried out in five health facilities in the Northern region of Cameroon. DNA was extracted from the Buffy coat of each participant using the QIAamp®DNA mini kit. The DNA extract was then subjected to polymorphic analyses. CCR2 genotypes were analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The Chi-Squared test was used for the assessment of the Hardy-Weinberg equilibrium. RESULTS: A total of 134 children under 15 years comprised of 38 HIV-exposed infected (28.36%) and 96 HIV-exposed un-infected (71.64%) participants were recruited. Prevalences of 44.78% wild type homozygous, 48.52% heterozygous and 6.7% mutant homozygous alleles were found in the overall population. An allelic frequency of 29.69% for the mutant allele CCR2-64I was found in HIV-exposed un-infected individuals as compared to 34.21% in HIV-infected children (p=0.47). CONCLUSION: The CCR2-64I allele is relatively common in the Northern Region of Cameroon, with a similar distribution among HIV-exposed un-infected and infected children. As this allele alone does not seem to confer protection against HIV-1 infection, further studies using genotype-combination of CCR2 polymorphism and other single nucleotide polymorphisms would be of great relevance in both HIV prevention and novel therapeutic strategies.

LETTER TO THE EDITOR Performance of the ViroSeq® HIV-1 Genotyping System v2.0 in Central Africa.

Resistance genotypes in pol gene of HIV-1 were obtained by the ViroSeq(®) HIV-1 Genotyping System v2.0 (Celera Diagnostics, Alameda, CA, USA) in 138 of 145 (95%) antiretroviral treatment-experienced adults in virological failure living in Central Africa (Cameroon, Central African Republic, Chad, Gabon). HIV-1 group M exhibited broad genetic diversity. Performance of the 7 ViroSeq(®) sequencing primers showed high failure rate, from 3% to 76% (D: 76%; F: 17%; A and H: 15%; G and B: 4%; C: 3%). These findings emphasize the need of updating the ViroSeq(®) HIV-1 genotyping system for non-B subtypes HIV-1.