Human Leukocyte Antigens -DQA1 and -DQB1 Alleles in Patients With Common Warts

Introduction The human papillomavirus induces the formation of lesions in different epithelia. Several studies describe an association of class II human leukocyte antigen with genital lesions, implying that they could also be related to the presence of common warts. The goal of this work was to determine the frequency of human leukocyte antigens (HLA)-DQA1 and HLA-DQB1 in Mexicans with common warts. Methods Thirty-two patients with a diagnosis of common warts, without any other systemic disease, and 100 healthy subjects from the same geographic area were recruited. The second exon of the HLA-DQA1 and HLA-DQB1 loci was typed by dot-blot and chemiluminescence. Results Alleles DQA1*03:01:01 (P = 0.021) and DQB1*03:02 (P = 0.036) were associated with the presence of skin warts. DQA1*04:01-DQB1*04:02 (P = 0.009) and DQA1*03:01:01-DQB1*03:02 (P = 0.044) were the most frequent haplotypes in patients. Conclusion In conclusion, the results of our study showed that the alleles DQA1 *03:01:01, DQB1*03:02, DQA1 *04:01, and DQB1*04:02 were associated with susceptibility to common warts, while DQA1*05:01 was significantly diminished in them. Consequently, the haplotypes DQA1*04:01-DQB1*04: 02 and DQA1*03:01:01-DQB1*03:02 were found to be associated with susceptibility, and DQA1*05:01-DQB1*03:01 increased significantly in controls. Therefore, the alleles of the DQA1 and DQB1 genes that are associated with susceptibility could be presenting human papillomavirus (HPV) peptides to T lymphocytes that activate a Th2-type response (anti-inflammatory cytokines), which allows the development of skin warts in this population.

Association between cycle threshold (Ct ) values and clinical and laboratory data in inpatients with COVID-19 and asymptomatic health workers

In‐house assays for the diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) by quantitative reverse‐transcription polymerase chain reaction (qRT‐PCR), are feasible alternatives, particularly in developing countries. Cycle threshold (C_t) values obtained by qRT‐PCR were compared with clinical and laboratory data from saliva of inpatients with COVID‐19 and asymptomatic health workers (AHW) were studied. Saliva specimens from 58 inpatients confirmed by qRT‐PCR for SARS‐CoV‐2 using nasopharyngeal specimens, and 105 AHW were studied by qRT‐PCR using three sets of primers for the N (N1, N2, and N3) gene of SARS‐CoV‐2, according to the CDC Diagnostic Panel protocol, showing a positivity of 88% for inpatients and 8% for AHW. Bivariate analysis revealed an association between C_t < 38.0 values for N2 and mechanical ventilation assistance among patients (p = .013). In addition, values of aspartate‐transaminase, lactate dehydrogenase, and ferritin showed significant correlations with C_t values of N1 and N3 genes in inpatients. Therefore, our results show that C_t values correlate with some relevant clinical data for inpatients with COVID‐19.

Cervical lymph node tuberculosis and TNF, IL8, IL10, IL12B and IFNG polymorphisms

Cervical lymph node tuberculosis (LNTB) is the most common manifestation of extrapulmonary tuberculosis, resulting from the interaction of environmental and genetic factors. The immune response against TB is regulated by several cytokines, which have single nucleotide polymorphisms (SNPs), leading to different levels of expression. The aim of this study was to evaluate the association of LNTB with the TNF, IL8, IL10, IL12B and IFNG gene polymorphisms in Mexican patients. We investigated the association of ten SNPs in 14 patients with LNTB and 138 healthy controls. Significant differences were found for the allele TNF-238A (P=0.03) and the genotypes TNF-238GA (P=0.03), IL8+396GG (P=0.01) and IL12B+1188CC (P=0.04). Allele IL8+781C showed some association trend (P=0.08). Haplotypes TNF-AA and IL10-GTA were of susceptibility, whereas haplotype IL8-ATT was of protection. No association was found with IFNG. The association of these polymorphisms with extrapulmonary TB was compared in different populations. Our results suggest that these cytokine SNPs may influence the manifestation of LNTB in Mexican patients; however, we are aware of the limitations of our study, so it is necessary to make a replica using a larger sample of patients, as well as an increased number of cytokines with SNPs.

Association of Cystathionine β-Synthase Gene Polymorphisms With Preeclampsia

Preeclampsia (PE) is a pregnancy disorder that increases maternal and fetal morbidity and mortality worldwide. High plasma levels of homocysteine (Hcy) are a risk factor for several cardiovascular diseases. Cystathionine β-synthase (CBS) plays an important role in Hcy homeostasis catalyzing the irreversible degradation of Hcy to cystathionine, protecting the endothelium from injury caused by hypoxia. Several mutations and polymorphisms may alter the expression of the CBS gene, resulting in variable levels of Hcy. The purpose of this study was to investigate the association of CBS gene polymorphisms with PE in Mexican women. A case–control study consisting of 129 pregnant women with PE (37 severe and 92 mild) and 173 women with uncomplicated pregnancies was performed. Polymorphisms, such as G797A, C785T, T833C, G919A, T959C, C1105T, and 844ins68 base pair, in the CBS gene were genotyped. The polymorphism G797A was monomorphic in cases with the presence of only G797A-G allele. Allele C785T-T and genotype C785T-C/T were associated with susceptibility in severe and mild PE. Alleles G797A-G and T959C-T were associated with susceptibility only in severe PE. Haplotype TGTWGTC was of susceptibility for severe PE and of protection for mild PE. Haplotypes CGTWGCC and CATWGTC seem to be protective for severe PE, but the latter is related to susceptibility in mild PE. The results suggest that C785T, G797A, and T959C mutations are contributing in different ways in severe and mild PE in our population and could be count as another related factor for this disease.

MSX1 gene polymorphisms in Mexican patients with non-syndromic cleft lip/palate

OBJECTIVE

Non-syndromic cleft lip/palate malformation (CL/P) is one of the most common birth defects in humans and has a complex etiology involving genetic and environmental factors. Mutations in the MSX1 gene are critical during craniofacial development. The purpose of this study was to investigate the contribution of MSX1 gene polymorphisms to the risk of developing CL/P in a sample of Mexican patients.

METHODS

The sample consisted of 282 subjects (69 cases and 213 relatives). Four single-nucleotide polymorphisms (SNP1, P147Q, SNP5 and P278S) were tested for association with CL/P in triad and case-pseudo-control analyses. Polymorphism typing was performed by restriction fragment length polymorphism and dot-blot techniques. Allele and genotype frequencies were calculated between patients and pseudo-controls and compared using the Chi square test with Yates correction. Odds ratios and 95% confidence intervals were obtained using SPSS software (v19). Triad analysis was also performed using the program HAPLIN (v5.3).

RESULTS

In the cases and pseudo-controls, an association was found between CL/P and the SNP1-G allele (P = 0.031) and the SNP1-G/G genotype (P = 0.032), a polymorphism located near MSX1. Triad analysis showed a tendency toward CL/P susceptibility for the genotype SNP1-G/G (P = 0.075) and an association between CL/P and the haplotype GCTC (P = 0.037). No associated haplotype was found in the cases and pseudo-controls. Two partial haplotypes, GT (SNP1-SNP5) (P = 0.032) and GC (SNP1-P278S) (P = 0.033), were associated with susceptibility in the heterozygous and homozygous types, respectively. In contrast, haplotype AT (SNP1-SNP5) was associated with protection (P = 0.012) in the homozygous type.

CONCLUSIONS

The results of this study suggest an association between CL/P susceptibility and SNP1, located near the MSX1 gene, in the Mexican population.

Leptin receptor gene polymorphisms and morbid obesity in Mexican patients

BACKGROUND

Human obesity is due to a complex interaction among environmental, behavioral, developmental and genetic factors, including the interaction of leptin (LEP) and leptin receptor (LEPR). Several LEPR mutations and polymorphisms have been described in patients with early onset severe obesity and hyperphagic eating behavior; however, some contradictory findings have also been reported. In the present study we explored the association of six LEPR gene polymorphisms in patients with morbid obesity.

FINDINGS

Twenty eight patients with morbid obesity and 56 non-obese Mexican Mestizo individuals were included. Typing of rs1137100, rs1137101, rs1805134, Ser492Thr, rs1805094 and rs1805096 LEPR polymorphisms was performed by PCR and allele specific hybridization. The LEPR Ser492Thr polymorphism was monomorphic with the presence of only the Ser492Thr-G allele. Allele C and genotype T/C for rs1805134 polymorphism were associated with susceptibility to morbid obesity (p = 0.02 and p = 0.03, respectively). No association was observed with any haplotype. Linkage disequilibrium (LD) showed that five polymorphisms (rs1137100, rs1137101, rs1805134, rs1805094 and rs1805096) were in absolute (D' = 1) but none in perfect (r² = 1) LD.

CONCLUSIONS

Our results suggest that rs1805134 polymorphism could be involved in the development of morbid obesity, whilst none of the alleles of the LEPR gene, rs1137100, rs1137101, rs1805094 and rs1805096 were associated as risk factors. However, more studies are necessary to confirm or reject this hypothesis.