Admixture and population structure in Mexican-Mestizos based on paternal lineages

Differences in Clinical Profiles and Biologic Treatment Approaches for Autoimmune Rheumatic Diseases Across Regions in Mexico: An Analysis of the BIOBADAMEX Cohort

OBJECTIVE

Being Mexico a very diverse developing country, the access to health care varies among geographical regions. We aimed to assess the differences in clinical features and treatment prescription in 3 regions of Mexico using data from the Mexican Adverse Events Registry (BIOBADAMEX).

METHODS

We included all BIOBADAMEX patients from 2016 to 2023, compared the prescription patterns, the sociodemographic, clinical, and treatment characteristics between the northern (NR), central (CR), and southern regions (SR), and addressed the treatment survival by calculating hazards ratios (HRs).

RESULTS

A total of 1084 patients were included: 389 (35.9%) from the NR, 569 (52.5%) from the CR, and 126 (11.6%) from the SR. The most common diagnosis was rheumatoid arthritis (61.0%). Patients from NR had longer disease duration ( p = 0.03); those from SR had higher BMI ( p < 0.001), DAS28 ( p < 0.001), BASDAI scores ( p = 0.02), and used more frequently glucocorticoids ( p < 0.001). Patients from CR had more comorbidities ( p = 0.001) and more regularly used conventional DMARDs ( p = 0.007). Among patients with at least 2 assessments (n = 441), treatment with bDMARDs and tsDMARDs was discontinued in 247 (56%), 53% due to lack of efficacy. There was no association between the country region and treatment survival, but the main factors related to treatment discontinuation were disease duration (HR, 0.9; 95% confidence interval, 0.6-0.9) and lack of response (HR, 1.4; 95% confidence interval, 1.2-1.7).

CONCLUSIONS

In Mexico, patients with rheumatic diseases show regional differences in their clinical features and prescription patterns, which may be related to regional disparities in health care access and sociodemographic characteristics.

Genetic Diversity and Forensic Parameters of 27 Y-STRs in Two Mestizo Populations from Western Mexico

BACKGROUND

Analyzing Y-chromosome short tandem repeats (Y-STRs) is essential in forensic genetics and population studies. The Yfiler™ Plus kit, which includes 27 Y-STR markers, enhances the discrimination power for forensic and kinship applications. However, this genetic system has not been analyzed in Mexican populations, which limits its application and representativeness in international databases.

OBJECTIVES

We wished to examine the genetic diversity and forensic parameters of the 27 Y-STRs included in the YFiler™ Plus kit in two populations from Western Mexico (Jalisco and Michoacán).

METHODS

Male DNA samples were amplified using the Yfiler™ Plus kit, followed by a fragment analysis via capillary electrophoresis (CE). The haplotype frequencies and forensic parameters were calculated. The haplogroups of all samples were predicted, and the distribution and percentages of ancestries were determined. The Rst genetic distances, including reference populations, were calculated and graphically represented in a multidimensional scaling (MDS) plot.

RESULTS

A total of 224 haplotypes were identified in all of the samples, of which 98.66% corresponded to unique haplotypes. Bi- and tri-allelic patterns were observed in both populations. The observed discriminatory capacity was 98.4% for Jalisco and 98.9% for Michoacán, while the haplotype diversity values were 0.9998 and 0.9997, respectively. The most frequent haplogroup was R1b, followed by Q, representing the European and Native American ancestries, in both populations.

CONCLUSIONS

This study is the first to report the haplotype diversity and forensic parameters of the 27 Y-STRs included in the Yfiler™ Plus kit in Mexican populations. These findings confirm the forensic utility of these markers for human identification, biological relationship testing, and criminal investigations, reinforcing their applicability in forensic casework.

Analysis of IL10 gene promoter haplotypes and changes in mRNA expression and soluble levels in patients with basal cell carcinoma

Interleukin-10 (IL-10) is an immunomodulatory molecule that may play an immunosuppressive role in nonmelanoma skin cancer (NMSC), specifically basal cell carcinoma (BCC). We analyzed the role of IL10 promoter variants in genetic determinants of BCC susceptibility and their association with IL10 mRNA and IL-10 serum levels. Three promoter variants (- 1082 A > G, - 819 T > C, and - 592 A > C) were examined in 250 BCC patients and 250 reference group (RG) individuals. IL10 relative gene expression was evaluated in total leucocytes in peripheral blood, and IL-10 levels were quantified in serum. The allelic and genotypic frequencies did not show significant differences between the groups. However, haplotype analysis revealed that the ATA haplotype was associated with a decreased risk of BCC (OR: 0.73, 95% CI 0.56-0.95, p = 0.02), whereas the ATC and ACA haplotypes were associated with an increased risk for the neoplasia (OR: 4.15, 95% CI 1.56-11.04, p < 0.01, and OR: 3.51, 95% CI 1.33-9.29, p < 0.01, respectively). BCC patients showed a 0.09-fold reduction in IL10 mRNA expression compared to the RG. Significant differences were in IL-10 median serum levels between the RG and BCC patients (0.4 vs 0.64 pg/mL, p = 0.02). Significant median serum differences were also observed between low- and high-grade histopathological BCC (0.34 vs 1.35 pg/mL, p = 0.02). The ATA, ATC, and ACA haplotypes, and serum IL-10 levels, could be markers of susceptibility to BCC in Western Mexican individuals. BCC patients had higher serum IL-10 levels than the RG, with levels increasing with the severity of lesions, confirming the role of IL-10 in immunosuppression in neoplasia.

Treating the Latin American Aesthetic Patient: A Review

The rich and diverse heritage of Latin American people contributes to a large variety of physical features, which translates to a patient population with a range of motivations for seeking cosmetic procedures and unique perspectives that influence their aesthetic preferences. As there is no one standard of beauty, it is important for physicians to understand the various factors that influence their patients' perceptions of beauty and desires to seek cosmetic treatment, especially because patient preference may differ from the physician perspective. Physicians in Latin America must consider the demographic, ethnic, and cultural factors that influence their patients to ensure culturally sensitive treatment approaches, natural-looking results, and patient satisfaction. This review includes a discussion of published literature, combined with the expert opinion of the authors, to provide a detailed description of the elements that impact aesthetic perceptions of patients living across the Latin American diaspora and highlights important gaps in research for future studies to address.

Population expansion, larger, and more homogeneous native American ancestry among Mexican mestizo populations based on 10 X-chromosome STR loci (X-STR decaplex system)

OBJECTIVE

To evaluate the genetic diversity, admixture, genetic relationships, and sex-biased demographic processes in Mexican Mestizo (admixed) populations based on 10 X-chromosome STRs (X-STRs).

METHODS

We analyzed the X-STRs Decaplex system in 104 Mexican Native Americans to obtain the ancestral reference needed to complete the demographic analyses above mentioned. We included reported Iberian and Latin American (admixed) populations from Central and South America, as well as datasets from Mexican Mestizos based on Y-linked STRs (Y-STRs), autosomal STRs (A-STRs), and mtDNA.

RESULTS

Higher X-linked Native American ancestry was observed among Latin American populations regarding that reported from A-STRs and Y-STRs. The interpopulation differentiation based on ancestry among Mexican Mestizos diminished according to the inheritance pattern: Y-STRs (highest), A-STRs, X-STRs, and mtDNA (lowest). This finding is related to the peculiar admixture process that occurred during and after the Spanish Conquest of Mexico (and most of Latin America), involving a large number of Spanish men (Y-chromosomes) with a lesser proportion of X-chromosomes than autosomes; besides to the limited number of Spanish women (XX) arrived in the Americas in subsequent and shorter periods. Population expansion was detected in Mexican Mestizos from all the country, except those from the southeast region characterized by elevated indigenous ancestry, marginalization, and poorness.

CONCLUSIONS

Population growth was detected in most Mexican Mestizos, besides more homogeneous and larger Native American ancestry based on X-linked inheritance than that based on autosomal STRs and Y-STRs.

IRF5 Variants Are Risk Factors for Systemic Lupus Erythematosus in Two Mexican Populations

INTRODUCTION

Interferon regulatory factor 5 ( IRF5 ) is one of the pivotal genes implicated in systemic lupus erythematosus (SLE) among diverse ethnic groups, including Europeans, Asians, Hispanics, and Africans. Notably, its significance appears particularly pronounced among Hispanic populations. Previous studies have identified several single-nucleotide variants within IRF5 , such as rs2004640G/T, rs2070197T/C, and rs10954213G/A, as associated with susceptibility to SLE among patients from Mexico City. However, the population of Yucatan, located in the Southeast of Mexico and characterized by a greater Amerindian genetic component, remains largely unexplored in this regard.

OBJECTIVES

Our study aimed to replicate the observed association between IRF5 variants and susceptibility to SLE among patients from Central Mexico and Yucatan. Furthermore, we investigated the impact of IRF5 rs59110799G/T, a variant that has not been previously studied in SLE individuals.

METHOD

Our study included 204 SLE patients and 160 controls from Central Mexico, as well as 184 SLE patients and 184 controls from Yucatan. All participants were females 18 years and older. We employed a TaqMan assay to detect the presence of the following single-nucleotide variants: rs2004640G/T, rs2070197T/C, rs10954213G/A, and rs59110799G/T. Furthermore, we utilized 2 distinct web tools and databases to predict the potential functional implications of IRF5 variants.

RESULTS

In SLE patients from Central Mexico, several IRF5 alleles showed significant associations with the disease following adjustment by the Bonferroni test: the rs2070197C allele (odds ratio [OR], 2.08), the rs10954213A allele (OR, 1.59), and the rs59110799G allele (OR, 1.71). Conversely, among patients from Yucatan, the following alleles showed associations: rs2004640T (OR, 1.51), rs2070197C (OR, 1.62), rs10954213A (OR, 1.67), and rs59110799G (OR, 1.44).

CONCLUSION

Our findings highlight genetic variations between Mexican populations and emphasize the role of IRF5 as a risk factor in SLE patients from both Central Mexico and Yucatan.

Circum-Mediterranean influence in the Y-chromosome lineages associated with prostate cancer in Mexican men: A Converso heritage founder effect?

Prostate cancer is the second most common neoplasia amongst men worldwide. Hereditary susceptibility and ancestral heritage are well-established risk factors that explain the disparity trends across different ethnicities, populations, and regions even within the same country. The Y-chromosome has been considered a prototype biomarker for male health. African, European, Middle Eastern, and Hispanic ancestries exhibit the highest incidences of such neoplasia; Asians have the lowest rates. Nonetheless, the contribution of ancestry patterns has been scarcely explored among Latino males. The Mexican population has an extremely diverse genetic architecture where all the aforementioned ancestral backgrounds converge. Trans-ethnic research could illuminate the aetiology of prostate cancer, involving the migratory patterns, founder effects, and the ethnic contributions to its disparate incidence rates. The contribution of the ancestral heritage to prostate cancer risk were explored through a case-control study (152 cases and 372 controls) study in Mexican Mestizo males. Seventeen microsatellites were used to trace back the ancestral heritage using two Bayesian predictor methods. The lineage R1a seems to contribute to prostate cancer (ORadjusted:8.04, 95%CI:1.41-45.80) development, whereas E1b1a/E1b1b and GHIJ contributed to well-differentiated (Gleason ≤ 7), and late-onset prostate cancer. Meta-analyses reinforced our findings. The mentioned lineages exhibited a connection with the Middle Eastern and North African populations that enriched the patrilineal diversity to the southeast region of the Iberian Peninsula. This ancestral legacy arrived at the New World with the Spanish and Sephardim migrations. Our findings reinforced the contribution of family history and ethnic background to prostate cancer risk, although should be confirmed using a large sample size. Nonetheless, given its complex aetiology, in addition to the genetic component, the lifestyle and xenobiotic exposition could also influence the obtained results.

High Interleukin 21 Levels in Patients with Systemic Lupus Erythematosus: Association with Clinical Variables and rs2221903 Polymorphism

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by autoantibody production and diverse tissue and organ inflammatory affections. Interleukin 21 (IL-21) is implicated in B cell survival, proliferation, differentiation, class switching, and immunoglobulin production; therefore, it is considered a key cytokine in the pathogenesis of SLE. However, its association with disease activity and clinical phenotypes remains unclear. We aimed to evaluate the association of IL-21 levels with the disease activity and clinical phenotypes in patients with SLE. Also, we analyzed the IL21 polymorphisms associated with increased IL-21 levels. Methods: The IL-21 serum levels were determined using the enzyme-linked immunosorbent assay (ELISA) method. The rs2221903 and rs2055979 polymorphisms were assessed in 300 healthy controls (HCs) and 300 patients with SLE by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The levels of IL-21 were monitored during follow-up visits in 59 patients with SLE. Results: The patients with SLE showed higher IL-21 levels compared to the HCs. The IL-21 levels did not correlate with Mex-SLEDAI and were not different in patients with inactive, mild-moderate, and severe disease. The IL-21 levels were increased in patients with hematological affection. The ROC curve analysis revealed that the IL-21 levels had good predictive power in discriminating among patients with SLE and HCs. In a follow-up analysis, the levels of IL-21 remained higher in the patients with SLE even when the patients were in remission. Also, the rs2221903 polymorphism was associated with increased IL-21 levels. Conclusions: This study highlights the importance of IL-21 as a key cytokine in SLE. IL-21 levels are higher in patients with SLE and remain increased regardless of disease activity. According to the ROC analysis, IL-21 is a potential biomarker of SLE. Further longitudinal studies are needed to explore the relationship between IL-21 and the clinical phenotypes of SLE.

ABCA1 variant rs9282541 is associated with metabolic syndrome in Maya children

INTRODUCTION

Metabolic syndrome (MetS) is a metabolic disorder encompassing risk factors for cardiovascular disease and type 2 diabetes (T2D). In Mexico, the MetS is a national health problem in adults and children. Environmental and genetic factors condition the MetS. However, studies to elucidate the contribution of genetic factors to MetS in Mexico are scarce. A recent study showed that variant rs9282541 (A-allele) in ATP-binding cassette transporter A1 (ABCA1) was associated with T2D in the Maya population in addition to low levels of high-density lipoprotein cholesterol (HDL-C). Thus, this study aimed to determine whether the genetic variant of ABCA1 A-allele (rs9282541, NM_005502.4:c.688C > T, NP_005493.2:p.Arg230Cys) is associated with MetS and its components in Mexican Maya children.

METHODS

The study was conducted in 508 children aged 9-13 from the Yucatán Peninsula. MetS was identified according to the de Ferranti criteria. Genotyping was performed using TaqMan assay by real-time PCR. Evaluation of genetic ancestry group was included.

RESULTS

The frequency of MetS and overweight-obesity was 45.9% and 41.6%, respectively. The genetic variant rs9282541 was associated with low HDL-C and high glucose concentrations. Remarkably, for the first time, this study showed the association of ABCA1 rs9282541 with MetS in Maya children with an OR of 3.076 (95% CI = 1.16-8.13 p = 0.023). Finally, this study reveals a high prevalence of MetS and suggests that variant rs9282541 of the ABCA1 gene plays an important role in the developing risk of MetS in Maya children.

Moderate altitude as a risk factor for isolated congenital malformations. Results from a case-control multicenter-multiregional study

BACKGROUND

Living in high-altitude regions has been associated with a higher prevalence of some birth defects. Moderate altitudes (1500-2500 m) have been associated with some congenital heart diseases and low birth weight. However, no studies have been conducted for other isolated congenital malformations.

OBJECTIVES

To estimate the prevalence at birth of isolated congenital malformations in low and moderate altitudes and to determine if moderate altitudes are a risk factor, such as high altitudes, for isolated congenital malformations adjusted for other factors.

METHODS

The study consisted of a case-control multicenter-multiregional study of 13 isolated congenital malformations. Cases included live births with isolated congenital malformations and controls at low (10-1433 m) and moderate altitudes (1511-2426 m) from a Mexican registry from January 1978 to December 2019. Prevalence per 10,000 (95% CI) per altitude group was estimated. We performed unadjusted and adjusted logistic regression models (adjusted for maternal age, parity, malformed relatives, socioeconomic level, and maternal diabetes) for each isolated congenital malformation.

RESULTS

Hydrocephaly and microtia had a higher at-birth prevalence, and spina bifida, preauricular tag, and gastroschisis showed a lower at-birth prevalence in moderate altitudes. Moderate altitudes were a risk factor for hydrocephaly (aOR 1.39), microtia (aOR 1.60), cleft-lip-palate (aOR 1.27), and polydactyly (aOR 1.32) and a protective effect for spina bifida (aOR 0.87) compared with low altitudes.

CONCLUSIONS

Our findings provide evidence that moderate altitudes as higher altitudes are an associated risk or protective factor to some isolated congenital malformations, suggesting a possible gradient effect.

IL10 promoter variants are associated with gene expression but they are not markers of susceptibility to acute coronary syndrome

Interleukin-10 (IL-10) is an immunomodulatory cytokine that plays a pivotal role in the pathogenesis of acute coronary syndromes (ACS). Here, we evaluated the role of IL10 promoter variants as markers for ACS susceptibility in Western Mexican patients as well as its association with IL10 mRNA and IL-10 plasma levels. Three promoter variants (- 1082 A > G, - 819 T > C and - 592 A > C) were analyzed in 300 ACS patients and 300 control group (CG) individuals. IL10 relative gene expression was evaluated in peripheral blood mononuclear cells (PBMC) and IL-10 levels were quantified in plasma. The allelic, genotypic and haplotypic frequencies did not show significant differences between groups. ACS patients had sevenfold higher mRNA IL10 level compared to CG (p = 0.0013). Homozygous C/C carriers in both - 819 T > C and - 592 A > C variants had 0.4-fold higher IL10 mRNA expression than heterozygous and polymorphic allele homozygous genotypes (p = 0.0357) in ACS group. There were significant differences in plasma IL-10 levels in CG and ACS group (1.001 vs 1.777 pg/mL, p = 0.0051). The variants were not markers of susceptibility to ACS in Western Mexican individuals. ACS patients showed higher IL10 expression than CG individuals which could be mediated by - 819 T > C and - 592 A > C variants and pharmacotherapy.

Interactions between TNFAIP3, PTPN22, and TRAF1-C5 gene polymorphisms in patients with primary Sjögren's syndrome

Objectives

The aim of our study was to investigate whether TNFAIP3, PTPN22, and TRAF1-5 single nucleotide polymorphisms (SNPs) are associated with susceptibility, severity, or serological markers in primary Sjögren's syndrome (pSS).

Patients and methods

The cases and controls study was conducted between December 2021 and June 2022. TNFAIP3 rs10499194C/T, rs6920220G/A, and rs2230926T/G, PTPN22 rs2476601C/T and rs33996649G/A, and TRAF1-C5 rs10818488G/A polymorphisms were genotyped in 154 female pSS patients (mean age: 45.2±6.8 years) and 313 female control subjects (mean age: 50.3±7.5 years) using the TaqMan® SNP genotyping assay. An association analysis between TNFAIP3, PTPN22, and TRAF1-C5 SNPs and susceptibility, clinical characteristics, and serological markers of pSS was performed. Interactions between TNFAIP3, PTPN22, and TRAF1-C5 SNPs were also evaluated in patients and controls.

Results

The genotype and allele frequencies showed no association with susceptibility, severity, or serological markers of pSS. Nevertheless, several interactions between TNFAIP3 and TRAF1-C5 or TNFAIP3, PTPN22, and TRAF1-C5 genotypes were associated with susceptibility to pSS (p<0.01).

Conclusion

Individual TNFAIP3, PTPN22, and TRAF1-C5 SNPs are not associated with susceptibility, severity, or serological markers of pSS. However, genetic interactions between TRAF1-C5 and TNFAIP3 or TNFAIP3, PTPN22, and TRAF1-C5 SNPs are risk factors for pSS.

STAT4 Gene Variant rs7574865 Is Associated with Rheumatoid Arthritis Activity and Anti-CCP Levels in the Western but Not in the Southern Population of Mexico

Rheumatoid Arthritis (RA) is a multifactorial autoimmune disease. Currently, several genes play an important role in the development of the disease. The objective was to evaluate the association of the STAT4 rs7574865 and rs897200 gene variants with RA susceptibility, DAS28, RF, and anti-CCP in Western and Southern Mexico populations. Genotyping was performed on 476 samples (cases = 240; controls = 236) using the Taqman® system and qPCR probes. Disease activity was assessed using DAS28 and HAQ DI. CRP, ESR, RF, and anti-CCP were determined for clinical assessment. Our study showed there is a statistically significant association with susceptibility to RA for the rs7574865 variant in the Western population for the GT and TT genotypes. The same genotypes also showed a moderate-to-high activity according to DAS28 and positive anti-CCP compared to the control group. This association was not found in the Southern population. This work confirms the association of the rs7574865 variant with RA, as well as a moderate-to-high activity and positive anti-CCP in the Western population but not in the Southern population. No association of the rs897200 variant was found in any of the studied populations.

Association of the BDNF rs6265 Polymorphism with Cognitive Impairment in Multiple Sclerosis: A Case-Control Study in Mexican Patients

Cognition is a set of brain processes that allow the individual to interact with their environment. Multiple sclerosis (MS) is a chronic inflammatory disease that affects the cerebral white matter of the brain cortex and spinal cord, leading to cognitive impairment (CI) in 40-60% of the patients. Many studies have determined that CI is linked to genetic risk factors. We aimed to evaluate the association between BDNF gene rs6265 polymorphism and cognitive impairment in Mexican patients with MS by performing a case-control study. Mestizo-Mexican patients diagnosed with MS based on McDonald's criteria were enrolled. Cases were MS patients with CI (n = 31) while controls were MS patients without CI (n = 31). To measure cognitive functioning in MS patients, a neuropsychological screening battery for MS (NSB-MS) was used. Genotyping of the rs6265 gene variant was performed using quantitative real-time PCR (qPCR) with TaqMan probes. The results showed no statistically significant differences in sociodemographic and disease variables between case and control groups. qPCR analysis showed that there were 68% Val/Val wild-type homozygotes, 29% Val/Met polymorphic heterozygotes, and 3% Met/Met polymorphic homozygotes. The presence of BDNF gene rs6265 polymorphism showed an increased probability (3.6 times) of global cognitive impairment.

Association of the rs8720 and rs12587 KRAS Gene Variants with Colorectal Cancer in a Mexican Population and Their Analysis In Silico

Colorectal cancer (CRC) is a major global health challenge and one of the top 10 cancers in Mexico. Lifestyle and genetic factors influence CRC development, prognosis, and therapeutic response; identifying risk factors, such as the genes involved, is critical to understanding its behavior, mechanisms, and prognosis. The association between KRAS gene variants (rs8720 and rs12587) and CRC in the Mexican population was analyzed. We performed in silico analysis and analyzed 310 healthy individuals and 385 CRC patients using TaqMan assays and real-time PCR. The CC and GG genotypes of rs8720 and rs12587 were identified as CRC risk factors (p < 0.05). The CC and TC genotypes of the rs8720 were associated with rectal cancer, age over 50 years, moderately differentiated histology, and advanced cancer stage. TG and GG genotypes of the rs12587 variant were a risk factor in the CRC group, in patients with stage I-II, males, and stage III-IV non-chemotherapy response. The TG haplotype is protected against CRC. The combined CCGG genotype was linked to CRC risk. In silico analysis revealed that the rs12587 and rs8720 variants could influence KRAS gene regulation via miRNAs. In conclusion, rs8720 and rs12587 variants of the KRAS gene were associated with CRC risk and could influence KRAS regulation via miRNAs.

Polymorphisms −374 T/A and −429 T/C of the Receptor for Advanced Glycation End-Products (RAGE) and Serum Levels of RAGE (sRAGE) Are Not Associated with Metabolic Syndrome

RAGE is a multi-ligand transmembrane glycoprotein that promotes biological signals associated with inflammatory responses and degenerative diseases. sRAGE is a soluble variant, proposed as an inhibitor of RAGE activity. −374 T/A and −429 T/C polymorphisms of the advanced glycation end products receptor AGER gene are associated with the development of some diseases, such as type of cancer, cardiovascular disease, and micro and macrovascular disease in diabetes among others but their role in metabolic syndrome (MS) is still unknown. We studied 80 healthy men without MS, and 80 men with MS according to the harmonized criteria. −374 T/A and −429 T/C polymorphisms were genotyped by RT-PCR, and sRAGE was measured by ELISA. Allelic and genotypic frequencies did not differ between Non-MS and MS groups (−374 T/A p = 0.48, p = 0.57 and −429 T/C p = 0.36, p = 0.59). Significant differences were found in fasting glucose levels and diastolic blood pressure among the genotypes of the −374 T/A polymorphism in the Non-MS group (p < 0.01 and p = 0.008). Glucose levels were different between −429 T/C genotypes in the MS group (p = 0.02). sRAGE levels were similar in both groups, but in the Non-MS group showed a significant difference between individuals with only 1 or 2 components of the metabolic syndrome (p = 0.047). However, no associations of any SNP with MS were found (recessive model p = 0.48, dominant model p = 0.82 for −374 T/A; recessive model p = 0.48, dominant model p = 0.42 for −429 T/C). −374 T/A and −429 T/C polymorphisms are not associated with MS in Mexican population and have no influence on serum sRAGE levels.

Aesthetic considerations when treating the Latin American patient: Thriving in diversity international roundtable series

BACKGROUND

The Hispanic/Latin American population is the fastest growing non-Caucasian group in the United States. Within this group, demand for aesthetic procedures is on the rise. High ethnic variability among these patients influences treatment approaches and patient priorities. Understanding these ethnic differences is central to providing optimal care.

AIMS

To discuss similarities and differences in anatomy and treatment preferences of Hispanic/Latin American patients both within the United States and internationally and explore how these differences may influence or inform aesthetic practices.

PATIENTS/METHODS

In support of clinicians who wish to serve a diverse patient population, a 6-part, international roundtable series focused on diversity in aesthetics was conducted from August 24, 2021 to May 16, 2022. In this roundtable, held in Medellin, Columbia, expert clinicians from across Latin America and the United States were invited to contribute and share best practices.

RESULTS

The results of the second roundtable in the series, the Latin American Patient, are described here. A special emphasis is placed on procedures that address the most commonly encountered concerns in these patients.

CONCLUSIONS

Hispanic and Latino patients represent a broad demographic with unique anatomical features, aesthetic preferences, and treatment priorities. Clinicians should consider these differences when treating this patient population.

Body Composition in Youths Aged 10‒17 Years by Deuterium Oxide Dilution, Air Displacement Plethysmography, and DXA: Validation of the Medical Body Composition Analyzer Bioimpedance Device by a 4-Compartment Model

BACKGROUND

The medical body composition analyzer (mBCA) incorporates advances in multifrequency technology and has been validated using a 4-compartment (4C) model in adults but not in youths aged <18 y.

OBJECTIVES

This study aimed to formulate a 4C model based on 3 reference methods and develop and validate a body composition prediction equation for the mBCA in youths aged 10‒17 y.

METHODS

The body density of 60 female and male youths was measured by air displacement plethysmography, total body water by deuterium oxide dilution, and BMC by DXA. Data from the equation group (n = 30) were used to formulate a 4C model. The all-possible-regressions method was used to select variables. The model was validated in a second cohort (n = 30) in a random split design. The accuracy, precision, and potential bias were evaluated by the Bland and Altman procedure.

RESULTS

Mean age, weight (W), height (H), waist circumference, and z-score of BMI were 13.6 ± 2.3 y, 54.5 ± 15.5 kg, 156 ± 11.9 cm, 75.5 ± 10.9 cm, and 0.70 ± 1.32 z, respectively. The prediction equation was as follows: FFM in kg (FFM_kg) = ([0.2081] ∗ [W] + [0.8814] ∗ [H²_cm/R_Ω] + [0.2055 ∗ Xc_Ω])-15.343; R² = 0.96; standardized root-mean-square error (SRMSE) = 2.18 kg. FFM did not differ between the 4C method (38.9 ± 12.0 kg) and the mBCA (38.4 ± 11.4 kg) (P > 0.05). The relationship between these 2 variables did not deviate from the identity line, was not significantly different from 0, and the slope was not significantly different from 1.0. In the precision prediction model of mBCA, the R² value was 0.98 and SRMSE was 2.1. No significant bias was found when regressing differences between methods and their means (P = 0.08).

CONCLUSIONS

The equation for the mBCA was accurate, precise, had no significant bias, had substantial strength of agreement and could be used in this age group when subjects were preferentially within the constraints of a specified body size.

ADIPOQ-rs2241766 polymorphism is associated with changes in cholesterol levels of Mexican adolescents

BACKGROUND

The ADIPOQ gene encodes a fat-derived protein hormone with a preponderant role in the homeostasis of glucose and fatty acids. However, previous association studies between ADIPOQ genetic variants and metabolic disorders have shown controversial results. In this study, we evaluated the effect of the ADIPOQ-rs2241766 polymorphism on diverse biochemical parameters (i.e., insulin resistance, atherogenic index, overweight and obesity) in an adolescent population from Mexico.

METHODS

A cross-sectional study with convenience sampling was carried out in 356 adolescents from Northern Mexico. They were classified by sex and BMI-z score. The biochemical parameters were measured from blood samples using conventional methods. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

In low and normal weight groups, GG carriers had a significantly higher cholesterol level (P ≤ 0.05) than TG and TT carriers. However, there was no association between ADIPOQ-rs2241766 polymorphism and atherogenic index, overweight, or obesity.

CONCLUSIONS

Our findings suggest that the cholesterol levels are under the influence of the ADIPOQ-rs2241766 polymorphism in Mexican adolescents and may explain how ADIPOQ variants increase the risk of developing metabolic disorders. Nevertheless, further studies are required to rule out the influence of other genetic and non-genetic factors.

MultiWaverX: modeling latent sex-biased admixture history

Sex-biased gene flow has been common in the demographic history of modern humans. However, the lack of sophisticated methods for delineating the detailed sex-biased admixture process prevents insights into complex admixture history and thus our understanding of the evolutionary mechanisms of genetic diversity. Here, we present a novel algorithm, MultiWaverX, for modeling complex admixture history with sex-biased gene flow. Systematic simulations showed that MultiWaverX is a powerful tool for modeling complex admixture history and inferring sex-biased gene flow. Application of MultiWaverX to empirical data of 17 typical admixed populations in America, Central Asia, and the Middle East revealed sex-biased admixture histories that were largely consistent with the historical records. Notably, fine-scale admixture process reconstruction enabled us to recognize latent sex-biased gene flow in certain populations that would likely be overlooked by much of the routine analysis with commonly used methods. An outstanding example in the real world is the Kazakh population that experienced complex admixture with sex-biased gene flow but in which the overall signature has been canceled due to biased gene flow from an opposite direction.

Analysis of TNFSF13B polymorphisms and BAFF expression in rheumatoid arthritis and primary Sjögren's syndrome patients

Background

The increased expression of B cell‐activating factor (BAFF) has been linked to autoantibody production in autoimmune diseases (ADs). The aim of this study was to investigate the association among TNFSF13B gene (OMIM: 603969) single nucleotide polymorphisms (SNPs), TNFSF13B mRNA, and soluble BAFF (sBAFF) expression in patients with rheumatoid arthritis (RA) and primary Sjögren's syndrome (pSS). The diagnostic value of sBAFF also was evaluated by the area under the curve (AUC) of receiver operating characteristic or receptor (ROC) curves.

Methods

Genotypes of the TNFSF13B rs9514827 (−2841 T > C), rs1041569 (−2701 A > T) and rs9514828 (−871 C > T) SNPs were determined by PCR‐RFLP assay. TNFSF13B mRNA and sBAFF expression were performed by RT‐qPCR and ELISA, respectively. The study included 320 RA patients, 101 pSS patients, and 309 healthy subjects (HS).

Results

The rs9514828 T allele and the TAT haplotype were associated with an increased risk to develop RA. In both ADs, the TNFSF13B mRNA levels were increased in comparison with HS. The rs9514828 (−871 C > T) polymorphism was associated with increased gene expression in RA patients. Also, sBAFF levels were higher in both ADs, however pSS patients showed the highest sBAFF levels. sBAFF showed higher diagnostic performance for pSS with an AUC of 0.968, with a similar accuracy of anti‐SSA/Ro antibody diagnosis (AUC = 0.974).

Conclusions

Our findings demonstrate that the TNFSF13B rs9514828 (−871 C > T) polymorphism is a risk factor for RA in the western Mexican population. sBAFF levels may be a potential diagnosis biomarker in pSS.

Genome wide association study on development and evolution of glutinous rice

BACKGROUND

Glutinous rice as a special endosperm type is consumed as a staple food in East Asian countries by consumers' preference. Genetic studies on glutinous rice could be conducive to improve rice quality and understand its development and evolution. Therefor, we sought to explore more genes related to glutinous by genome wide association study and research the formation history for glutinous.

RESULTS

Here, genome-wide association study was performed to explore the associated loci/genes underlying glutinous rice by using 2108 rice accessions. Combining the expression patterns analysis, 127, 81, and 48 candidate genes were identified to be associated with endosperm type in whole rice panel, indica, and japonica sub-populations. There were 32 genes, including three starch synthesis-related genes Wx, SSG6, and OsSSIIa, detected simultaneously in the whole rice panel and subpopulations, playing important role in determining glutinous rice. The combined haplotype analyses revealed that the waxy haplotypes combination of three genes mainly distributed in Southeast Asia (SEA), SEA islands (SER) and East Asia islands (EAR). Through population structure and genetic differentiation, we suggest that waxy haplotypes of the three genes firstly evolved or were directly inherited from wild rice in japonica, and then introgressed into indica in SER, SEA and EAR.

CONCLUSIONS

The cloning and natural variation analysis of waxy-related genes are of great significance for the genetic improvement of quality breeding and comprehend the history in glutinous rice. This work provides valuable information for further gene discovery and understanding the evolution and formation for glutinous rice in SEA, SER and EAR.

Is History the Same as Evolution? No. Is it Independent of Evolution? Certainly Not

History is full of violence and oppression within and between groups, and although group conflicts enhance within-group cooperation (mediated by oxytocin, which promotes parochial altruism) the hierarchy within groups ensures that spoils accrue very unevenly. Darwin suggested, and we now know, that sexual selection is as powerful as selection by mortality, and the main purpose of survival is reproduction. Male reproductive skew is greater than that among females in all societies, but the difference became much greater after the hunting-gathering era, and the rise of so-called "civilization" was everywhere a process of predatory expansion, producing kingdoms and empires where top males achieved astounding heights of reproductive success. This was shown by historical and ethnographic data now strongly confirmed by genomic science. Psychological research confirms that group identity, out-group stigmatization, leadership characterized by charisma, the will to power, narcissism, sociopathy, and cruelty, and followership characterized by hypnotic obedience, loss of individuality, and cruelty are integral parts of human nature. We can thank at least ten or twelve millennia of microevolutionary processes such as those described above, all more prominent in males than females. Followers in wars have faced a difficult risk-benefit analysis, but if they survived and won they too could increase their reproductive success through the rape and other sexual exploitation that have accompanied almost all wars. For modern leaders, social monogamy and contraception have separated autocracy from reproductive success, but only partly, and current worldwide autocratic trends still depend on the evolved will to power, obedience, and cruelty.

Refractive status of patients attending eye clinics of the Public Health System from Aguascalientes, Mexico

PURPOSE

This paper aims to evaluate the prevalence of REs in a clinic from Aguascalientes, Mexico by analysing clinical records from the local public health system. Refractive errors (REs) are quite common globally, but no data have been published regarding their frequency in clinics from Mexico. A priori, the frequency of ametropias should be high as admixture ancestry from this region is mainly European and Amerindian, the regions with high prevalence worldwide.

METHODS

This cross-sectional study was conducted on 2195 subjects from records of public optometry services during the year 2018. Information obtained included age, gender, sphere, cylinder and axis. The prevalence of myopia, hyperopia and astigmatism was determined by gender and age groups in paediatric and adult patients. Chi-square testing was applied to determine significant differences in prevalence across age groups and gender. A p-value <0.05 was considered significant.

RESULTS

In subjects under 18 years of age, the prevalence of emmetropia, astigmatism, myopia and hyperopia was 20.1%, 51.1%, 7.0% and 11.8%, respectively. In adults, emmetropia was present at a frequency of 20.1%, while 57.1% presented astigmatism, 12.4% hyperopia and 8.6% presented myopia. A significant association was observed between the presence of REs and age and gender.

CONCLUSIONS

In this first report of prevalence of REs from western Mexico, astigmatism was the most prevalent RE in children, adolescents and adults while the least common was myopia. Important differences were found in prevalence in comparison to national and international reports.

Fitness and Power: The Contribution of Genetics to the History of Differential Reproduction

Textual evidence from pre-modern societies supports the prediction that status differences among men translate to variance in reproductive success. In recent years, analysis of genetic data has opened up new ways of studying this relationship. By investigating cases that range over several millennia, these analyses repeatedly document the replacement of local men by newcomers and reveal instances of exceptional reproductive success of specific male lineages. These findings suggest that violent population transfers and conquests could generate considerable reproductive advantages for male dominants. At the same time, this does not always seem to have been the case. Moreover, it is difficult to link such outcomes to particular historical characters or events, or to identify status-biased reproductive inequalities within dominant groups. The proximate factors that mediated implied imbalances in reproductive success often remain unclear. A better understanding of the complex interplay between social power and genetic fitness will only arise from sustained transdisciplinary engagement.

Population diversity of three variants of the SLC47A2 gene (MATE2-K transporter) in Mexican Mestizos and Native Americans

BACKGROUND

MATE2-K is an efflux transporter protein of organic cation expressed mainly in the kidney and encoded by the SLC47A2 gene. Different variants of this gene have shown an impact on the pharmacokinetics of various drugs, including metformin, which represents one of the most widely used drugs in treating type 2 diabetes. The SLC47A2 gene variants have been scarcely studied in Mexican populations, especially in Native American groups. For this reason, we analyzed the distribution of the variants rs12943590, rs35263947, and rs9900497 within the SLC47A2 gene in 173 Native Americans (Tarahumara, Huichol, Maya, Puerépecha) and 182 Mestizos (admixed) individuals from Mexico.

METHODS AND RESULTS

Genotypes were determined through TaqMan probes (qPCR). The Hardy-Weinberg agreement was confirmed for all three SLC47A2 gene variants in all the Mexican populations analyzed. When worldwide populations were included for comparison purposes, for alleles and genotypes a relative interpopulation homogeneity was observed for rs35263947 (T allele; range 23.3-51.1%) and rs9900497 (T allele; range 18.6-40.9%). Conversely, heterogeneity was evident for rs12943590 (A allele, range 22.1-59.1%), where the most differentiated population was the Huichol, with high frequencies of the risk genotype associated with decreased response to metformin treatment (A/A = 40.9%).

CONCLUSIONS

Although the SLC47A2 gene variants allow predicting favorable response to the metformin treatment in Mexican populations, the probable high frequency of ineffectiveness should be discarded in Huichols.

COVID-19 and gastrointestinal symptoms in Mexico, a systematic review: does location matter?

BACKGROUND

Covid-19 in Mexico is on the rise in different parts of the country. We aimed to study the symptoms and comorbidities that associate with this pandemic in 3 different regions of Mexico.

METHODS

We analyzed data from SARS-CoV-2 positive patients evaluated at healthcare centers and hospitals of Mexico (n = 1607) including Northwest Mexico (Sinaloa state), Southeast Mexico (Veracruz state) and West Mexico (Jalisco state) between March 1 and July 30, 2020. Mexico consists of a total population that exceeds 128 million. Demographics, comorbidities and clinical symptoms were collected. Statistical descriptive analysis and correlation analyses of symptoms, comorbidities and mortality were performed.

RESULTS

A total of 1607 hospitalized patients positive for COVID-19 across all 3 regions of Mexico were included. The average age was 54.6 years and 60.4% were male. A mortality rate of 33.1% was observed. The most common comorbidities were hypertension (43.2%), obesity (30.3%) and diabetes (31.4%). Hypertension was more frequent in West (45%), followed by Northwest (37%) and Southeast Mexico (29%). Obesity was around 30% in Northwest and West whereas an 18% was reported in Southeast. Diabetes was most common in West (34%) followed by Northwest (22%) and Southeast (13%). This might be related to the highest mortality rate in Northwest (31%) and West (37%) when compared to Southeast. Most common symptoms in our overall cohort were fever (80.8%), cough (79.8%), headache (66%), dyspnea (71.1%), myalgia (53.8%), joints pain (50.8%) and odynophagia (34.8%). Diarrhea was the main gastrointestinal (GI) symptom (21.3%), followed by abdominal pain (18%), and nausea/ vomiting (4.5%). Diarrhea and abdominal pain were more common in West (23.1 and 21%), followed by Southeast (17.8, and 9.8%) and Northwest (11.4 and 3.1%).

CONCLUSION

Our study showed a high mortality rate likely related to high frequencies of comorbidities (hypertension, obesity and diabetes). Mortality was different across regions. These discrepancies might be related to the differences in the frequencies of comorbidities, and partially attributed to differences in socio-economic conditions and quality of care. Thus, our findings stress the need for improved strategies to get better outcomes in our population.

Contribution of rs3211938 polymorphism at CD36 to glucose levels, oxidized low-density lipoproteins, insulin resistance, and body mass index in Mexican mestizos with type-2 diabetes from western Mexico

Introduction

Background: type-2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by hyperglycemia, insulin resistance (IR), and abnormal fatty acid metabolism in which the CD36 receptor has been implicated in glucose and lipid dysregulation. Objective: to evaluate the contribution of polymorphism CD36 rs3211938 to metabolic profile in T2DM Mexican mestizos from western Mexico. Methods: we included 115 individuals classified as non-T2DM (NT2DM) adults and T2DM patients. Polymorphism CD36 rs3211938 was assessed by PCR-RFLP. Anthropometric and metabolic markers were measured by routine methods, and insulin and oxidized LDL (ox-LDL) were measured by ELISA. Results: the distribution of genotypes between NT2DM and T2DM patients was different (p < 0.001), as was the allele frequency (p = 0.002). NT2DM TG carriers showed the lowest levels of basal insulin and HOMA-IR index in comparison with TT carriers (p < 0.05 and p < 0.05, respectively). In the T2DM group TG carriers showed high BMI, WHR, and weight values (p = 0.001; p ≤ 0.05 and p < 0.05, respectively), and the highest levels of basal glucose, HDL-cholesterol, ox-LDL, and HOMA-IR (p < 0.001; p < 0.001; p < 0.001, and p = 0.001, respectively) in comparison with diabetic TT carriers. Conclusion: the CD36 rs3211938 TG genotype is associated with high levels of glucose, ox-LDL, HDL-cholesterol, and IR, and with increased BMI in Mexican mestizo T2DM patients from western Mexico.

"Distribution of paternal lineages in Mestizo populations throughout Mexico: an in silico study based on Y-STR haplotypes"

The Mexican-Mestizo population arose following European contact with the Americas due to the admixture of principally Spaniards, Native Americans, and Africans around 500 years ago. Because the paternal lineage distribution of the Mexican population has been poorly investigated, this study inferred the haplogroups of ten populations based on 1859 haplotypes (Y-STR data) using two haplogroup predictor programs. In the Mexican population sample, we found predominantly European ancestry (50.1%), followed by Native American (32.5%), Eurasian (13.4%), African (2.1%), East African-South Eurasian (1.3%), and Asian (0.6%) ancestries. In general, our results support a contrary north-to-south gradient throughout the Mexican territory of European and Native-American ancestries, respectively. Moreover, the presence of West-European R1b and Sub-Saharan African E1b1a haplogroups agrees with historical and genetic data of gene flow during the European conquest. This study represents the effort to analyze these paternal lineages on a large scale by taking advantage of Y-STR haplotype data to determine the distribution and ancestry proportions in this country.

Expression of miR-148b-3p is correlated with overexpression of biomarkers in prostate cancer

Prostate cancer (PCa) is one of the leading causes of death among men. Genes such as PCA3, PSA, and Fra-1 are suggested to serve as potential tools for the detection of PCa, as they are deregulated during this pathology. A similar event occurs with small non-coding RNAs, called miRNAs, specifically miR-195-5p, miR-133a-3p, and miR-148b-3p, which were analyzed in a Chinese population and suggested to be possible candidates for PCa diagnosis. We evaluated the expression levels of three miRNAs and three genes in tissue samples of PCa and benign prostate disease, such as benign prostatic hyperplasia, or prostatitis, in order to determine their potential as candidates for PCa detection. Our results showed a statistically significant overexpression of 279-fold increase in PSA levels and a 1,012-fold increase in PCA3 levels in PCa patients compared to benign prostate disease patients (p = 0.001 and p = 0.002, respectively). We observed a positive correlation between the expression of miR-148b-3p and the expression of PSA and PCA3 genes, two established biomarkers in PCa. The expression of miR-148b-3p was not related to clinical characteristics, such as age and weight, as observed for the other miRNAs analyzed, suggesting its potential as a biomarker for detection of this pathology.

Association of BLK and BANK1 Polymorphisms and Interactions With Rheumatoid Arthritis in a Latin-American Population

Introduction

BLK has been identified as a risk factor to rheumatoid arthritis (RA) primarily in Asian or European-derived populations. However, this finding has not been evaluated in other populations such as Latin-Americans, except for Colombians. On the other hand, BANK1 single nucleotide variants (SNVs) have been scarcely studied in RA patients.

Objective

The aim of this study was to determine whether the BLK rs2736340T/C, rs13277113A/G, and BANK1 rs10516487G/A (R61H) and rs3733197G/A (A383T) polymorphisms are risk factors to RA in a sample of patients from Central Mexico.

Materials and Methods

We studied 957 women; 487 controls and 470 patients with RA by means of a TaqMan® SNP genotyping assay with fluorescent probes for the BLK rs13277113A/G, rs2736340T/C and BANK1 10516487G/A (R61H) and rs3733197G/A (A383T) variants.

Result

The BLK rs2736340T/C and rs13277113A/G variants were associated with risk for RA: C vs T; OR 1.39, p = 0.001, and G vs A; OR 1.37, p = 0.004, respectively. In addition, there was also an association between BANK1 R61H and RA: A vs G; OR 1.49, p = 0.003, but no with BANK1 A383T. We also identified an interaction significant between genotypes of BLK rs2736340T/C-BANK1 rs10516487G/A and RA: OR 1.65, p = 0.0001.

Conclusions

Our data suggest that both BLK and BANK1 confer susceptibility to RA in Mexican patients. The individual association of BANK1 rs1054857G/A with RA had not been previously reported in a particular population (except for pooled patients from several countries), therefore, our study presents the first evidence of association between this BANK1 variant and RA.

External validation of the relative fat mass (RFM) index in adults from north-west Mexico using different reference methods

Background

Analysis of body composition is becoming increasingly important for the assessment, understanding and monitoring of multiple health issues. The body mass index (BMI) has been questioned as a tool to estimate whole-body fat percentage (FM%). Recently, a simple equation described as relative fat mass (RFM) was proposed by Woolcott & Bergman. This equation estimates FM% using two anthropometric measurements: height and waist circumference (WC). The authors state that due to its simplicity and better performance than BMI, RFM could be used in daily clinical practice as a tool for the evaluation of body composition. The aim of this study was to externally validate the equation of Woolcott & Bergman to estimate FM% among adults from north-west Mexico compared with Dual-energy X-ray absorptiometry (DXA) as an alternative to BMI and secondly, to make the same comparison using air displacement plethysmography (ADP), Bioelectrical Impedance Analysis (BIA) and a 4-compartment model (4C model).

Methods

Weight, height and WC were measured following standard procedures. The RFM index was calculated for each of the 61 participating subjects (29 females and 32 males, ages 20–37 years). The RFM was then regressed against each of the four body composition methods for estimating FM%.

Results

Compared with BMI, RFM was a better predictor of FM% determined by each of the body composition methods. In terms of precision the best equation was RFM regressed against DXA (y = 1.12 + 0.99 x; R² = 0.84 p<0.001). Accuracy (represented by the closeness to the zero-intercept) was 1.12 (95% CI: -2.44, to 4.68) and thus, not significantly different from zero. For the rest of the methods, precision in the prediction of FM% was improved compared to BMI, with significant increases in the R² and reduction of the root mean squared error (RMSE). However, the intercepts of each regression did not show accuracy since they were different from zero, for ADP: -9.95 (95%CI: -15.7 to -4.14), for BIA: -12.6 (95%CI: -17.5 to -7.74) and for the 4C model: -13.6 (95%CI: -18.6 to -8.60). Irrespectively, FM% measured by each of the body composition methods was higher for DXA than the other three methods (p<0.001).

Conclusions

This external validation proved that the performance of the RFM equation used in this study to estimate FM% was more consistent than BMI in this Mexican population, showing a stronger correlation with DXA than with the other body composition methods.

ITGAM is a risk factor to systemic lupus erythematosus and possibly a protection factor to rheumatoid arthritis in patients from Mexico

Introduction

ITGAM has consistently been associated with susceptibility to systemic lupus erythematosus (SLE) in many ethnically diverse populations. However, in populations with higher Amerindian ancestry (like Yucatan) or highly admixed population (like Mexican), ITGAM has seldom been evaluated (except few studies where patients with childhood-onset SLE were included). In addition, ITGAM has seldom been evaluated in patients with rheumatoid arthritis (RA). Here, we evaluated whether four single nucleotide polymorphisms (SNPs), located within ITGAM, were associated with SLE and RA susceptibility in patients from Mexico.

Methods

Our study consisted of 1,462 individuals, which included 363 patients with SLE (292 from Central Mexico and 71 from Yucatan), and 621 healthy controls (504 from Central Mexico and 117 from Yucatan). Our study also included 478 patients with RA from Central Mexico. TaqMan assays were used to obtain the genotypes of the four SNPs: rs34572943 (G/A), rs1143679 (G/A), rs9888739 (C/T), and rs1143683 (C/T). We also verified the genotypes by Sanger sequencing. Fisher's exact test and permutation test were employed to evaluate the distribution of genotype, allele, and haplotype between patients and controls.

Results

Our data show that all four ITGAM SNPs are significantly associated with susceptibility to SLE using both genotypic and allelic association tests (corrected for multiple testing, but not for population stratification). A second study carried out in patients from Yucatan, a southeastern part of Mexico (with a high Amerindian ancestry), also replicated SLE association with all four SNPs, including the functional SNP, rs1143679 (OR = 24.6 and p = 9.3X10^-6). On the other hand, none of the four SNPs are significant in RA after multiple testing. Interestingly, the GACC haplotype, which carries the ITGAM rs1143679 (A) minor allele, showed an association with protection against RA (OR = 0.14 and p = 3.0x10^-4).

Conclusion

Our data displayed that ITGAM is a risk factor to SLE in individuals of Mexican population. Concurrently, a risk haplotype in ITGAM confers protection against RA.

Paternal lineages and forensic parameters based on 23 Y-STRs (Powerplex® Y23) in Mestizo males from Mexico City

We analyzed 307 Mexican-Mestizo (admixed) males from Mexico City with the Powerplex® Y23 system. The complete list of Y-STR haplotypes was uploaded into the YHRD database (accession number YA004275). The discriminatory capacity (98.70 %) and gene diversity (D = 99.99 %) were calculated, improving the haplotype diversity regarding previous studies in Mexico based on 17 Y-STRs and 12 Y-STRs. Haplogroup distribution assignment was inferred by means of two different online-available algorithms. The Native American Q* haplogroup was the most frequent (66.2 %), followed by the European R1b lineage (19.5 %). In addition, eight Eurasian (3.9%) and two African (6.6%) haplogroups were observed in this population sample from Mexico City. Interestingly, AMOVA test showed a low but significant differentiation among Mexican-Mestizos (Fst = 1.52%; p = 0.0000), suggesting that four population clusters allow to explain their genetic structure according to geographic criteria: north, west, center, and south.

Macrophage migration inhibitory factor promoter polymorphisms are associated with disease activity in rheumatoid arthritis patients from Southern Mexico

Background

Macrophage migration inhibitory factor (MIF) is a cytokine capable of stimulating inflammatory cytokine and matrix metalloproteinase production from macrophages and synovial fibroblasts, which leads to persistent inflammation and bone degradation, two of the major pathological processes in rheumatoid arthritis (RA). The aim of this study was to evaluate the association of MIF promoter polymorphisms (−794CATT_5‐8rs5844572 and −173G > C, rs755622), circulating MIF levels, and mRNA expression with RA susceptibility and disease activity.

Methods

A case–control study was conducted in 200 RA patients and 200 control subjects (CS) from Southern Mexico. Genotyping was performed by conventional PCR and PCR‐RFLP methods. MIF mRNA expression was quantified by real‐time PCR and MIF serum levels were determined by an ELISA kit.

Results

The 7,7 (−794CATT_5‐8) and −173CC (−173G > C) genotypes were associated with higher disease activity in RA patients. MIF serum levels were increased, and MIF mRNA expression was reduced in RA patients as compared to CS. In addition, RA patients with moderate disease activity had higher MIF levels than those with low disease activity. The −794CATT_5‐8 and −173G > C MIF polymorphisms were not associated with RA susceptibility.

Conclusion

These results suggest an important role of MIF polymorphisms and MIF serum levels with disease activity in RA.

Association of soluble CD40 levels with -1 C > T CD40 polymorphism and chronic kidney disease in systemic lupus erythematosus

Background

CD40 is a transmembrane protein mainly expressed on the antigen‐presenting cells surface. CD40 plays a crucial role in immunoglobulin class switching and antibodies production. Genetic polymorphisms in the CD40 gene have been associated with increased risk of systemic lupus erythematosus (SLE) in several populations. This study aimed to evaluate the association of CD40 polymorphisms (−1 C > T, rs1883832 and 6,048 G > T, rs4810485) with SLE susceptibility, as well as with mRNA expression and soluble CD40 (sCD40) levels.

Methods

The study included 293 patients with SLE and 294 control subjects (CS). Genotyping was performed by PCR‐RFLP method. CD40 mRNA expression was determined by quantitative real‐time PCR, and ELISA quantified sCD40 levels.

Results

The CD40 polymorphisms −1 C > T and 6,048 G > T were associated with SLE susceptibility. There was no difference between CD40 mRNA expression and CD40 polymorphisms. The sCD40 levels were lower in SLE patients with TT haplotype, whereas higher sCD40 levels were associated with damage and impaired renal function according to SLICC and KDIGO. The sCD40 levels were negatively correlated with eGFR.

Conclusion

The CD40 gene polymorphisms increase the risk of SLE in the western Mexican population. The sCD40 levels are associated with −1 C > T polymorphism and chronic kidney disease.

Hepatitis C virus clearance and less liver damage in patients with high cholesterol, low-density lipoprotein cholesterol and APOE ε4 allele

BACKGROUND

Cholesterol is related to improvements in the rate of sustained virological response and a robust immune response against the hepatitis C virus (HCV). APOE gene polymorphisms regulate cholesterol levels modifying the course of the HCV infection. The relationship between cholesterol, APOE alleles, and the outcome of HCV infection has not been evaluated in the admixed population of Mexico.

AIM

To investigate the role of APOE -ε2, -ε3, and -ε4 alleles and the metabolic profile in the outcome of HCV infection.

METHODS

A total of 299 treatment-naïve HCV patients were included in this retrospective study. Patients were stratified in chronic hepatitis C (CHC) (n = 206) and spontaneous clearance (SC) (n = 93). A clinical record was registered. Biochemical tests were assessed by dry chemistry assay. APOE genotypes were determined using a Real-Time polymerase chain reaction assay.

RESULTS

Total cholesterol, low-density lipoprotein cholesterol (LDL-c), triglycerides, and hypercholesterolemia were higher in SC than CHC patients as well as the frequency of the APOE ε4 allele (12.4% vs 7.3%). SC patients were overweight (54.8%). The ε4 allele was associated with SC (OR = 0.55, 95%CI: 0.31-0.98, P = 0.042) and mild fibrosis (F1-F2) in CHC patients (OR 0.091, 95%CI 0.01-0.75, P = 0.020). LDL-c ≥ 101.5 mg/dL (OR = 0.20, 95%CI: 0.10-0.41, P < 0.001) and BMI ≥ 26.6 kg/m2 (OR= 0.37, 95%CI: 0.18-0.76, P < 0.001) were associated with SC status; while ALT ≥ 50.5 IU/L was negatively associated (OR = 5.67, 95%CI: 2.69-11.97, P < 0.001).

CONCLUSION

In SC patients, the APOE ε4 allele and LDL-c conferred a protective effect in the course of the HCV infection in the context of excess body weight.

DRD2/ANKK1 TaqI A1 polymorphism associates with overconsumption of unhealthy foods and biochemical abnormalities in a Mexican population

PURPOSE

The dopamine receptor 2/ankyrin repeat domain and content kinase 1 (DRD2/ANKK1) TaqIA polymorphism (rs1800497) has been associated with rewarding behaviors. This study aimed to investigate the association of DRD2/ANKK1 TaqIA polymorphism with the dietary intake, the intake frequency of food groups and biochemical profile in Mexican mestizo subjects.

METHODS

A cross-sectional/analytical study with 276 Mexican subjects was performed. Dietary intake was assessed with a 24-h recall and a food frequency questionnaire (FFQ). An allelic discrimination assay evaluated DRD2/ANKK1 TaqIA genotypes. Anthropometric and biochemical data were evaluated.

RESULTS

Genotype frequencies were A1A1 (18.48%), A1A2 (45.29%) and A2A2 (36.23%). TaqI A1 allele carriers had a higher intake of carbohydrates (p = 0.038), meats (p = 0.005), fried dishes (p = 0.039), and sugars (p = 0.009). Male TaqI A1 carriers consumed more carbohydrates (p = 0.009) and meats (p = 0.018) while females consumed fewer legumes (p = 0.005). TaqI A1 carriers had glucose (p = 0.037) and triglycerides (p = 0.011) abnormalities. TaqI A1 was associated with higher risk of consumption of unhealthy foods such as fried dishes (OR 3.79, 95% CI 1.53-9.35, p = 0.002) and meats (OR 2.31, 95% CI 1.32-4.05, p = 0.003), and lower healthy foods (OR 1.89, 95% CI 1.04-3.29, p = 0.038). TaqI A1 allele was associated with risk of abnormal glucose, triglycerides, and VLDL levels (OR 2.148, 95% CI 1.068-4.322, p = 0.036; OR 1.999, 95% CI 1.194-3.348, p = 0.011; OR 2.021, 95% CI 1.203-3.392, p = 0.007), respectively.

CONCLUSIONS

The presence of the TaqI A1 allele in Mexicans is a genetic risk factor for detrimental dietary quality that may predispose to metabolic disturbances.

LEVEL OF EVIDENCE

Level III, case-control analytic study.

Haplotype block 1 variant (HB-1v) of the NKG2 family of receptors

The natural killer group 2 (NKG2) family of receptors, encoded within the NK complex gene region (NKC), modulate the cytotoxic activity of NK cells. Two haplotype blocks throughout the NKC, hb-1 and hb-2 have been associated with different levels of overall natural cytotoxicity. Here, we evaluated allelic and genotype frequencies at rs1049174, rs2617160, rs2617170, rs2617171, rs1983526 (hb-1 haplotype), and rs2255336 and rs2246809 (hb-2 haplotype) in 928 subjects examined from Mexico City. The most frequent alleles and genotypes were as follows: C, CG to rs1049174; G, GG to rs2255336; T, AT to rs2617160; G, GG to rs2246809; C, CT to rs2617170; G, CG to rs2617171; and G, CG to rs1983526. Linkage disequilibrium analysis revealed that rs1049174, rs2617160, rs2617170, and rs2617171 constituted the haplotype block-1 variant (hb-1v) (r² ≥ 0.89). Two predominant haplotypes of hb-1v were identified based on the allele content and included CTCG and GATC. This study is the first to evaluate the allelic and genotype frequency distribution of rs1049174, rs2255336, rs2617160, rs2246809, rs2617170, rs2617171, and rs1983526 in the population of Mexico City.

Disparities in prediabetes and type 2 diabetes prevalence between indigenous and nonindigenous populations from Southeastern Mexico: The Comitan Study

•

Indigenous origin conferred lower probability of prediabetes and type 2 diabetes.

•

Social determinants were associated with lower probability of type 2 diabetes.

•

Family history of diabetes was associated with prediabetes and type 2 diabetes.

Aims

In this research we assessed the prevalence of prediabetes and type 2 diabetes and its association with social determinants such as indigenous origin and residence area in population from Comitan, Chiapas, Mexico.

Methods

The Comitan Study is a population-based study carried out from 2010 to 2012 that included 1844 participants aged ≥ 20 years, 880 indigenous and 964 nonindigenous participants. Ethnicity was ascertained by self-report and speaking an indigenous language was also recorded. Prediabetes was defined as fasting serum glucose 5.6–6.9 mmol/l or 2-hour post load serum glucose 7.8–11.0 mmol/l. Type 2 diabetes was defined as fasting serum glucose ≥ 7.0 mmol/l or 2-h post load serum glucose ≥ 11.1 mmol/l or previous clinical diagnosis.

Results

Age-sex-adjusted prevalence of prediabetes and type 2 diabetes was 18.0% (95%CI 15.3–20.6) and 11.0% (95%CI 8.9–131.1) in nonindigenous and 10.6% (95%CI 8.4–12.7) and 4.7% (95%CI 3.3–6.1) in indigenous individuals, respectively. After stratifying by ethnicity, in both indigenous and nonindigenous participants the probability of prediabetes and type 2 diabetes increased with age and BMI. In both indigenous and nonindigenous participants the probability of type 2 diabetes was lower in those living in rural compared with urban areas.

Conclusions

The prevalence of prediabetes and type 2 diabetes was significantly lower in indigenous than in nonindigenous participants. Also, the prevalence of type 2 diabetes was lower in those living in rural areas. Health benefits of a traditional lifestyle may partially account for these differences.