Frequency of CCR5Δ32 allele in healthy Bosniak population

Bosnian study of APOE distribution (BOSAD): a comparison with other European populations

BACKGROUND

The ε2, ε3 and ε4 alleles of APOE gene have been associated with several diseases in different populations. Data on the frequency of alleles are used in both a clinical and evolutionary context. Although the data on frequency of these alleles are numerous, there are no reports for the population of Bosnia and Herzegovina.

AIM

To estimate the frequency of APOE alleles in a healthy Bosnian population and compare it to data for other European populations.

SUBJECTS AND METHODS

Overall, 170 unrelated Bosnian subjects (108 female and 62 male), aged 53.0 (±5.0) years were included in this study. Genotypes were determined by real-time PCR.

RESULTS

In our group the prevalence of heterozygotes E2/E3, E2/E4 and E3/E4 was 20.6%, 3.5% and 12.9%, respectively, while the prevalence of homozygotes E2/E2, E3/E3, E4/E4 was 0.6%, 61.2% and 1.2%, respectively, with a mean frequency of ε2, ε3 and ε4 alleles of 12.6%, 78.0% and 9.4%, respectively.

CONCLUSIONS

In studied European populations we observed a linear, gradually increasing trend in the frequency of ε4 allele from South to North (Pearson's test 0,7656, p value <0.00001), and the Bosnian population fits into this pattern perfectly.

Possible Impact of 190G > A CCR2 and Δ32 CCR5 Mutations on Decrease of the HBV Vaccine Immunogenicity-A Preliminary Report

Background: Chemokine genetic variations are involved in infectious diseases such as hepatitis B virus (HBV). Several allelic variants might, in theory, affect the outcome of vaccination. Objectives: This study was carried out to examine the associations of Δ32 CCR5 and 190G > A CCR2 polymorphisms with a response to a primary course of three HBV vaccinations. Methods: Between December 2014 and December 2016, patients from three randomly selected primary care clinics in the West Pomeranian region (Poland), 1 month after receiving the third dose of HBV vaccine, were enrolled. Enzyme-linked immunosorbent assay (ELISA) system version 3.0 was used to detect anti-HBs and anti-HBc totals. The identification of polymorphisms were performed by a polymerase chain reaction technique using a single primer extension assay. Genotype distributions of responders versus non-responders to HBV vaccination were compared on the basis of anti-HBs level. Results: In 149 patients (mean age 60 years) the mean anti-HBs level was 652.2 ± 425.9 mIU/mL (range: 0–1111.0 mIU/mL). There were 14.1% (n = 21) non-responders to the HBV vaccine (anti-HBs < 10.0 mIU/mL). The wild type/Δ32 genotype of CCR5 gene was found in 18.1% participants, and 1.3% were Δ32/Δ32 homozygotes. The frequency of allele A of the CCR2 gene was 11.1%. Lower anti-HBs levels in Δ32/Δ32 homozygotes were observed (Me = 61 mIU/mL vs. Me = 660.2 mIU/mL; p = 0.048). As age was found to be a correlate to the anti-HBs titer (r = −0.218, p = 0.0075; 95% CI: −0.366–−0.059)—an analysis of a co-variance was performed which found a statistically significant (p = 0.04) difference in anti-HBs titres between Δ32/Δ32 homozygotes and other CCR5 genotypes. The association between anti-HBs titres and CCR2 genotypes was not statistically significant. Conclusions: Our study—which is a preliminary report that suggest this topic deserves further observation with larger sample sizes, different ethnicities, and other single nucleotide poly-morphisms (SNPs)—suggests the possible involvement of CCR5 polymorphism in impairing the immunologic response to HBV vaccination, predominantly in relation to the passage of time.