Polymorphic genetic variation in immune system genes: a study of two populations of Espirito Santo, Brazil

Abstract

Mapping single nucleotide polymorphisms (SNPs) in genes potentially involved in immune responses may help understand the pathophysiology of infectious diseases in specific geographical regions. In this context, we have aimed to analyze the frequency of immunogenetic markers, focusing on genes CD209 (SNP -336A/G), FCγRIIa (SNP -131H/R), TNF-α (SNP -308A/G) and VDR (SNP Taq I) in two populations of the Espirito Santo State (ES), Brazil: general and Pomeranian populations. Peripheral blood genomic DNA was extracted from one hundred healthy individuals of the general population and from 59 Pomeranians. Polymorphic variant identification was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). SNP genotype frequencies were in Hardy-Weinberg Equilibrium. There was no statistically significant difference in allelic and genotypic distributions between the two populations studied. Statistically significant differences were observed for SNP genotype distribution in genes CD209, TNF-α and VDR when comparing the ES populations with other Brazilian populations. This is the first report of CD209, FcγRIIa, TNF-α and VDR allelic frequencies for the general and Pomeranian populations of ES.

Single nucleotide polymorphisms in immune system genes and their association with clinical symptoms persistence in dengue-infected persons

“…Age, gender, reinfection, acute phase medication, race and viral characteristics may influence dengue outcome of [30]. In our study, we have found a longer persistence of symptoms in females patients, which is in agreement with García et al…”

“…SNPs genotype distribution in symptomatic dengue patients remained similar to the normal ES population genotype distribution, as demonstrated in previous studies performed by us like Dettogni et al [30] and other work not yet published.…”

Molecular epidemiology of HFE gene polymorphic variants (C282Y, H63D and S65C) in the population of Espírito Santo, Brazil

“…In addition, there was no statistically significant difference in allele and genotype distribution between the Pomeranian subpopulation and general population in our study. This result confirms other data that reported gene flow between the general and Pomeranian populations of ES (Stur et al, 2012;Dettogni et al, 2013).…”

Frequency of SNP -336A/G in the promoter region of CD209 in a population from northeastern Brazil

“…In the study, the frequency of allele -336G was 29.7% in a naturally mixed population, a frequency that does not differ statistically from the frequency we observed (20.2% in a mixed population in northeastern Brazil). Although the frequency of CD209 SNP -336A/G found in this study was similar to the frequency found in other Brazilian regions (Xavier-Carvalho et al, 2013;Oliveira et al, 2014), it was significantly lower than that found in a population in the southeast, where the observed frequency was 37.5% (P < 0.05) (Dettogni et al, 2013). However, a higher frequency of allele -336G has been observed even in neighboring Piauí states such as Pernambuco; the allele frequency in the study performed by Silva et al (2012) was 31.4% (P = 0.052).…”