Beyond the identifiable proteome: Delving into the proteomics of polymyxin-resistant and non-resistant Acinetobacter baumannii from Brazilian hospitals.

This work discloses a unique, comprehensive proteomic dataset of Acinetobacter baumannii strains, both resistant and non-resistant to polymyxin B, isolated in Brazil generated using Orbitrap Fusion Lumos. From nearly 4 million tandem mass spectra, the software DiagnoMass produced 240,685 quality-filtered mass spectral clusters, of which PatternLab for proteomics identified 44,553 peptides mapping to 3479 proteins. Crucially, DiagnoMass shortlisted 3550 and 1408 unique mass spectral clusters for the resistant and non-resistant strains, respectively, with only about a third with sequences (and PTMs) identified by PatternLab. Further open-search attempts via FragPipe yielded an additional ∼20% identifications, suggesting the remaining unidentified spectra likely arise from complex combinations of post-translational modifications and amino-acid substitutions. This highlights the untapped potential of the dataset for future discoveries, particularly given the importance of PTMs, which remain elusive to nucleotide sequencing approaches but are crucial for understanding biological mechanisms. Our innovative approach extends beyond the identifications that are typically subjected to the bias of a search engine; we discern which spectral clusters are differential and subject them to increased scrutiny, akin to spectral library matching by comparing captured spectra to themselves. Our analysis reveals adaptations in the resistant strain, including enhanced detoxification, altered protein synthesis, and metabolic adjustments. SIGNIFICANCE: We present comprehensive proteomic profiles of non-resistant and resistant Acinetobacter baumannii from Brazilian Hospitals strains, and highlight the presence of discriminative and yet unidentified mass spectral clusters. Our work emphasizes the importance of exploring this overlooked data, as it could hold the key to understanding the complex dynamics of antibiotic resistance. This approach not only informs antimicrobial stewardship efforts but also paves the way for the development of innovative diagnostic tools. Thus, our findings have profound implications for the field, as far as methods for providing a new perspective on diagnosing antibiotic resistance as well as classifying proteomes in general.

Prediction of the occurrence of leprosy reactions based on Bayesian networks.

Introduction: Leprosy reactions (LR) are severe episodes of intense activation of the host inflammatory response of uncertain etiology, today the leading cause of permanent nerve damage in leprosy patients. Several genetic and non-genetic risk factors for LR have been described; however, there are limited attempts to combine this information to estimate the risk of a leprosy patient developing LR. Here we present an artificial intelligence (AI)-based system that can assess LR risk using clinical, demographic, and genetic data. Methods: The study includes four datasets from different regions of Brazil, totalizing 1,450 leprosy patients followed prospectively for at least 2 years to assess the occurrence of LR. Data mining using WEKA software was performed following a two-step protocol to select the variables included in the AI system, based on Bayesian Networks, and developed using the NETICA software. Results: Analysis of the complete database resulted in a system able to estimate LR risk with 82.7% accuracy, 79.3% sensitivity, and 86.2% specificity. When using only databases for which host genetic information associated with LR was included, the performance increased to 87.7% accuracy, 85.7% sensitivity, and 89.4% specificity. Conclusion: We produced an easy-to-use, online, free-access system that identifies leprosy patients at risk of developing LR. Risk assessment of LR for individual patients may detect candidates for close monitoring, with a potentially positive impact on the prevention of permanent disabilities, the quality of life of the patients, and upon leprosy control programs.

Experimental approaches to assess melanocytes mosaicism in segmental vitiligo

Abstract Vitiligo is an autoimmune disease of the skin that results in localized or disseminated white macules. One common feature of several existing classification protocols is the distribution of the disease into two main subtypes, non-segmental vitiligo (NSV) and segmental vitiligo (SV). SV is characterized by depigmentation spreading within one or more skin segments while NSV is widespread. Several clinical-epidemiological observations suggest that SV has distinct autoimmune pathophysiology compared to NSV. Furthermore, the clinical distribution pattern of SV lesions closely resembles other melanocyte mosaicism diseases. These observations led us to hypothesize that SV is caused by a localized autoimmune reaction targeting epidermal mosaicism melanocytes. Here, we proposed examples of experimental approaches to assess mosaicism in SV patients.

Allele-dependent interaction of LRRK2 and NOD2 in leprosy.

Leprosy, caused by Mycobacterium leprae, rarely affects children younger than 5 years. Here, we studied a multiplex leprosy family that included monozygotic twins aged 22 months suffering from paucibacillary leprosy. Whole genome sequencing identified three amino acid mutations previously associated with Crohn's disease and Parkinson's disease as candidate variants for early onset leprosy: LRRK2 N551K, R1398H and NOD2 R702W. In genome-edited macrophages, we demonstrated that cells expressing the LRRK2 mutations displayed reduced apoptosis activity following mycobacterial challenge independently of NOD2. However, employing co-immunoprecipitation and confocal microscopy we showed that LRRK2 and NOD2 proteins interacted in RAW cells and monocyte-derived macrophages, and that this interaction was substantially reduced for the NOD2 R702W mutation. Moreover, we observed a joint effect of LRRK2 and NOD2 variants on Bacillus Calmette-Guérin (BCG)-induced respiratory burst, NF-κB activation and cytokine/chemokine secretion with a strong impact for the genotypes found in the twins consistent with a role of the identified mutations in the development of early onset leprosy.

Experimental approaches to assess melanocytes mosaicism in segmental vitiligo.

Vitiligo is an autoimmune disease of the skin that results in localized or disseminated white macules. One common feature of several existing classification protocols is the distribution of the disease into two main subtypes, non-segmental vitiligo (NSV) and segmental vitiligo (SV). SV is characterized by depigmentation spreading within one or more skin segments while NSV is widespread. Several clinical-epidemiological observations suggest that SV has distinct autoimmune pathophysiology compared to NSV. Furthermore, the clinical distribution pattern of SV lesions closely resembles other melanocyte mosaicism diseases. These observations led us to hypothesize that SV is caused by a localized autoimmune reaction targeting epidermal mosaicism melanocytes. Here, we proposed examples of experimental approaches to assess mosaicism in SV patients.

Resolving taxonomic confusion: establishing the genus Phytobacter on the list of clinically relevant Enterobacteriaceae.

Although many clinically significant strains belonging to the family Enterobacteriaceae fall into a restricted number of genera and species, there is still a substantial number of isolates that elude this classification and for which proper identification remains challenging. With the current improvements in the field of genomics, it is not only possible to generate high-quality data to accurately identify individual nosocomial isolates at the species level and understand their pathogenic potential but also to analyse retrospectively the genome sequence databases to identify past recurrences of a specific organism, particularly those originally published under an incorrect or outdated taxonomy. We propose a general use of this approach to classify further clinically relevant taxa, i.e., Phytobacter spp., that have so far gone unrecognised due to unsatisfactory identification procedures in clinical diagnostics. Here, we present a genomics and literature-based approach to establish the importance of the genus Phytobacter as a clinically relevant member of the Enterobacteriaceae family.

Association of MICA and HLA-B alleles with leprosy in two endemic populations in Brazil.

Leprosy is a prevalent disease in Brazil, which ranks as the country with the second highest number of cases in the world. The disease manifests in a spectrum of forms, and genetic differences in the host can help to elucidate the immunopathogenesis. For a better understanding of MICA association with leprosy, we performed a case-control and a family-based study in two endemic populations in Brazil. MICA and HLA-B alleles were evaluated in 409 leprosy patients and in 419 healthy contacts by PCR-SSOP-Luminex-based technology. In the familial study, analysis of 46 families was completed by direct sequencing of all exons and 3'/5'untranslated regions, using the Ilumina MiSeq platform. All data were collected between 2006 and 2009. Statistical analysis was performed using the Chi-square or Fisher's exact test together with a multivariate analysis. Family-based association was assessed by transmission disequilibrium test (TDT) software FBAT 2.0.4. We found associations between the haplotype MICA*002-HLA-B*35 with leprosy in both the per se and the multibacillary (MB) forms when compared to healthy contacts. The MICA allele *008 was associated with the clinical forms of paucibacillary (PB). Additionally, MICA*029 was associated with the clinical forms of MB. The association of MICA*029 allele (MICA-A4 variant) with the susceptibility to the MB form suggests this variant for the transmembrane domain of the MICA molecule may be a risk factor for leprosy. Two MICA and nine HLA-B variants were found associated with leprosy per se in the Colônia do Prata population. Linkage disequilibrium analysis revealed perfect linkage disequilibrium (LD) between HLA-B markers rs2596498 and rs2507992, and high LD (R2  = .92) between these and the marker rs2442718. This familial study demonstrates that MICA association signals are not independent from those observed for HLA-B. Our findings contribute the knowledge pool of the immunogenetics of Hansen's disease and reveals a new association of the MICA*029 allele.

HLA-DPB1 and HLA-C alleles are associated with leprosy in a Brazilian population.

Despite intense efforts, the number of new cases of leprosy has remained significantly high over the past 20 years. Host genetic background is strongly linked to the pathogenesis of this disease, which is caused by Mycobacterium leprae (M. leprae), and there is a consensus that the most significant genetic association with leprosy is attributed to the major histocompatibility complex (MHC). Here, we investigated the association of human leukocyte antigen (HLA) class I and II genes with leprosy in a Brazilian population encompassing 826 individuals from a hyperendemic area of Brazil; HLA typing of class I (-A, -B, -C) and class II (-DRB1, -DQA1, -DQB1, -DPA1, and -DPB1) loci was conducted. Initially, the associations were tested using the chi-square test, with p-values adjusted using the false discovery rate (FDR) method. Next, statistically significant signals of the associations were submitted to logistic regression analyses to adjust for sex and molecular ancestry data. The results showed that HLA-C*08, -DPB1*04, and -DPB1*18 were associated with protective effects, while HLA-C*12 and -DPB1*105 were associated with susceptibility to leprosy. Thus, our findings reveal new associations between leprosy and the HLA-DPB1 locus and confirm previous associations between the HLA-C locus and leprosy.

HLA-DPB1 and HLA-C alleles are associated with leprosy in a Brazilian population

Despite intense efforts, the number of new cases of leprosy has remained significantly high over the past 20 years. Host genetic background is strongly linked to the pathogenesis of this disease, which is caused by Mycobacterium leprae (M. leprae), and there is a consensus that the most significant genetic association with leprosy is attributed to the major histocompatibility complex (MHC). Here, we investigated the association of human leukocyte antigen (HLA) class I and II genes with leprosy in a Brazilian population encompassing 826 individuals from a hyperendemic area of Brazil; HLA typing of class I (-A, -B, -C) and class II (-DRB1, -DQA1, -DQB1, -DPA1, and -DPB1) loci was conducted. Initially, the associations were tested using the chi-square test, with p-values adjusted using the false discovery rate (FDR) method. Next, statistically significant signals of the associations were submitted to logistic regression analyses to adjust for sex and molecular ancestry data. The results showed that HLA-C*08, -DPB1*04, and -DPB1*18 were associated with protective effects, while HLA-C*12 and -DPB1*105 were associated with susceptibility to leprosy. Thus, our findings reveal new associations between leprosy and the HLA-DPB1 locus and confirm previous associations between the HLA-C locus and leprosy(AU).

Association of MICA and HLA­B alleles with leprosy in two endemic populations in Brazil

Leprosy is a prevalent disease in Brazil, which ranks as the country with the second highest number of cases in the world. The disease manifests in a spectrum of forms, and genetic differences in the host can help to elucidate the immunopathogenesis. For a better understanding of MICA association with leprosy, we performed a case­control and a family­based study in two endemic populations in Brazil. MICA and HLA­B alleles were evaluated in 409 leprosy patients and in 419 healthy contacts by PCR­SSOP­Luminex­based technology. In the familial study, analysis of 46 families was completed by direct sequencing of all exons and 3'/5'untranslated regions, using the Ilumina MiSeq platform. All data were collected between 2006 and 2009. Statistical analysis was performed using the Chi­square or Fisher's exact test together with a multivariate analysis. Family­based association was assessed by transmission disequilibrium test (TDT) software FBAT 2.0.4. We found associations between the haplotype MICA*002­HLA­B*35 with leprosy in both the per se and the multibacillary (MB) forms when compared to healthy contacts. The MICA allele *008 was associated with the clinical forms of paucibacillary (PB). Additionally, MICA*029 was associated with the clinical forms of MB. The association of MICA*029 allele (MICA­A4 variant) with the susceptibility to the MB form suggests this variant for the transmembrane domain of the MICA molecule may be a risk factor for leprosy. Two MICA and nine HLA­B variants were found associated with leprosy per se in the Colônia do Prata population. Linkage disequilibrium analysis revealed perfect linkage disequilibrium (LD) between HLA­B markers rs2596498 and rs2507992, and high LD (R2 = .92) between these and the marker rs2442718. This familial study demonstrates that MICA association signals are not independent from those observed for HLA­B. Our findings contribute the knowledge pool of the immunogenetics of Hansen's disease and reveals a new association of the MICA*029 allele(AU).

Association study between vitiligo and autoimmune-related genes CYP27B1, REL, TNFAIP3, IL2 and IL21.

The aetiology of vitiligo has not been fully elucidated, and several hypotheses have been investigated; among them, the most explored assumes an autoimmune basis for the disease. Supporting this hypothesis is the frequent co-occurrence of autoimmune diseases with vitiligo. In addition, various genetic loci associated with vitiligo harbour key immune response genes. Our general hypothesis is that autoimmunity-associated genes participate in the control of vitiligo susceptibility. To investigate this hypothesis, we tested for association between vitiligo and genes CYP27B1, REL, TNFAIP3 and IL2/IL21, all previously related to autoimmune diseases associated with vitiligo. The study was performed using two independent population samples: a family-based discovery set (211 trios) and a replication set (131 cases/119 controls). Statistically significant association with vitiligo was detected between markers of the REL and IL2 gene in the family-based sample. Both association signals were concentrated among patients displaying autoimmune comorbidity and non-segmental vitiligo. Evidence for validation was detected for IL2 marker. Our findings suggest REL and IL2 as new vitiligo susceptibility genes and reinforce the hypothesis of a shared genetic mechanism controlling vitiligo and other autoimmune diseases.

Human Genetic Susceptibility of Leprosy Recurrence.

Host genetic susceptibility to leprosy has been intensively investigated over the last decades; however, there are no studies on the role of genetic variants in disease recurrence. A previous initiative identified three recurrent cases of leprosy for which none of the M. leprae strains, as obtained in the first and the second diagnosis, had any known genomic variants associated to resistance to Multidrug therapy; in addition, whole genome sequencing indicated that the same M. leprae was causing two out of the three recurrences. Thus, these individuals were suspected of being particularly susceptible to M. leprae infection, either as relapse or reinfection. To verify this hypothesis, 19 genetic markers distributed across 11 loci (14 genes) classically associated with leprosy were genotyped in the recurrent and in three matching non-recurrent leprosy cases. An enrichment of risk alleles was observed in the recurrent cases, suggesting the existence of a particularly high susceptibility genetic profile among leprosy patients predisposing to disease recurrence.

Emergence and Transmission of Drug-/Multidrug-resistant Mycobacterium leprae in a Former Leprosy Colony in the Brazilian Amazon.

BACKGROUND: Leprosy has been treated with multidrug therapy, which has been distributed for free across the globe and regarded as highly efficient. However, the impossibility of growing Mycobacterium leprae in axenic media has historically impaired assessments of M. leprae resistance, a parameter only recently detectable through molecular methods. METHODS: A systematic, population-based search for M. leprae resistance in suspected leprosy relapse cases and contacts was performed in Prata Village, an isolated, hyperendemic, former leprosy colony located in the Brazilian Amazon. Results led to an extended active search involving the entire Prata population. Confirmed leprosy cases were investigated for bacterial resistance using a combination of in vivo testing and direct sequencing of resistance genes folP1, rpoB, and gyrA. A molecular epidemiology analysis was performed using data from 17 variable number tandem repeats (VNTR). RESULTS: Mycobacterium leprae was obtained from biopsies of 37 leprosy cases (18 relapses and 19 new cases): 16 (43.24%) displayed drug-resistance variants. Multidrug resistance to rifampicin and dapsone was observed in 8 relapses and 4 new cases. Single resistance to rifampicin was detected in 1 new case. Resistance to dapsone was present in 2 relapses and 1 new case. Combined molecular resistance and VNTR data revealed evidence of intra-familial primary transmission of resistant M. leprae. CONCLUSIONS: A comprehensive, population-based systematic approach to investigate M. leprae resistance in a unique population revealed an alarming scenario of the emergence and transmission of resistant strains. These findings may be used for the development of new strategies for surveillance of drug resistance in other populations.

Emergence and transmission of drug-/multidrug-resistant Mycobacterium leprae in a former leprosy colony in the Brazilian Amazon

BACKGROUND: Leprosy has been treated with multidrug therapy (MDT) distributed for free across the globe and regarded as highly efficient. However, the impossibility to grow M. leprae in axenic media has historically impaired assessment of M. leprae resistance, a parameter only recently detectable through molecular methods. METHODS: A systematic, population-based search for M. leprae resistance in suspected leprosy relapse cases and contacts was performed in Prata Village, an isolated, hyper-endemic former leprosy colony located in the Brazilian Amazon. Results led to an extended active search involving the entire Prata population. Confirmed leprosy cases were investigated for bacterial resistance using a combination of in vivo testing and direct sequencing of resistance genes folP1, rpoB and gyrA. Molecular epidemiology analysis was performed using data from 17 variable number tandem repeats (VNTR). RESULTS: M. leprae was obtained from biopsies of 37 leprosy cases (18 relapses and 19 new); 16 (43.24%) displayed drug-resistance variants. Multi-drug resistance to rifampicin and dapsone was observed in 8 relapses and 4 new cases. Single resistance to rifampicin was detected in one new case. Resistance to dapsone was present in two relapses and one new case. Combined molecular resistance and VNTR data revealed evidence of intra-familial primary transmission of resistant M. leprae. CONCLUSIONS: A comprehensive, population-based systematic approach to investigate M. leprae resistance in a unique population revealed an alarming scenario of emergence and transmission of resistant strains. These findings may be used for the development of new strategies for surveillance of drug resistance in other populations.

Complex segregation analysis of facial melasma in Brazil: evidence for a genetic susceptibility with a dominant pattern of segregation.

Despite high prevalence, the etiopathology of melasma is not fully understood. Nevertheless, many factors have been associated with the disease, including: sun exposure, sex steroids hormones, drugs, stress, and pregnancy. The high occurrence within familiars (40-60%) suggests a genetic predisposition to the disease. This study explored, through complex segregation analysis (CSA), the inheritance model that best fit the family segregation pattern of facial melasma when accounting for the main epidemiological risk factors. We evaluated 686 subjects from 67 families, and 260 (38%) of them had facial melasma. The CSA model, adjusted for age, skin phototype, sex, sun exposure at work, hormonal oral contraceptive, and pregnancy, evidenced a genetic component that was best fitted to a dominant pattern of segregation. Melasma results from an interaction between exposure factors (e.g. pregnancy, hormones, and sun exposure) over genetically predisposed individuals.

Molecular investigation of isolates from a multistate polymicrobial outbreak associated with contaminated total parenteral nutrition in Brazil.

BACKGROUND: Between November 2013 and June 2014, 56 cases of bacteremia (15 deaths) associated with the use of Total Parenteral Nutrition (TPN) and/or calcium gluconate (CG) were reported in four Brazilian states. METHODS: We analyzed 73 bacterial isolates from four states: 45 from blood, 25 from TPN and three from CG, originally identified as Acinetobacter baumannii, Rhizobium radiobacter, Pantoea sp. or Enterobacteriaceae using molecular methods. RESULTS: The first two bacterial species were confirmed while the third group of species could not be identified using standard identification protocols. These isolates were subsequently identified by Multi-Locus Sequence Analysis as Phytobacter diazotrophicus, a species related to strains from similar outbreaks in the United States in the 1970's. Within each species, TPN and blood isolates proved to be clonal, whereas the R. radiobacter isolates retrieved from CG were found to be unrelated. CONCLUSION: This is the first report of a three-species outbreak caused by TPN contaminated with A. baumannii, R. radiobacter and P. diazotrophicus. The concomitant presence of clonal A. baumannii and P. diazotrophicus isolates in several TPN and blood samples, as well as the case of one patient, where all three different species were isolated simultaneously, suggest that the outbreak may be ascribed to a discrete contamination of TPN. In addition, this study highlights the clinical relevance of P. diazotrophicus, which has been involved in outbreaks in the past, but was often misidentified as P. agglomerans.

Genetic Susceptibility to Leprosy-From Classic Immune-Related Candidate Genes to Hypothesis-Free, Whole Genome Approaches.

Genetics plays a crucial role in controlling susceptibility to infectious diseases by modulating the interplay between humans and pathogens. This is particularly evident in leprosy, since the etiological agent, Mycobacterium leprae, displays semiclonal characteristics not compatible with the wide spectrum of disease phenotypes. Over the past decades, genetic studies have unraveled several gene variants as risk factors for leprosy per se, disease clinical forms and the occurrence of leprosy reactions. As expected, several of these genes are immune-related; yet, hypothesis-free approaches have led to genes not classically linked to immune response. The PARK2, originally described as a Parkinson's disease gene, illustrates the case: Parkin-the protein coded by PARK2-was defined as an important player regulating innate and adaptive immune responses only years after its description as a leprosy susceptibility gene. Interestingly, even with the use of powerful hypothesis-free study designs such as genome-wide association studies, most of the major gene effect controlling leprosy susceptibility remains elusive. One hypothesis to explain this "hidden heritability" is that rare variants not captured by classic association studies are of critical importance. To address this question, massively parallel sequencing of large segments of the human genome-even whole exomes/genomes-is an alternative to properly identify rare, disease-causing mutations. These mutations may then be investigated through sophisticated approaches such as cell reprogramming and genome editing applied to create in vitro models for functional leprosy studies.

Emended description of the genus Phytobacter, its type species Phytobacter diazotrophicus (Zhang 2008) and description of Phytobacter ursingii sp. nov.

The species Phytobacter diazotrophicus and the associated genus Phytobacter were originally described by Zhanget al. [Arch Microbiol189 (2008), 431-439] on the basis of few endophytic nitrogen-fixing bacteria isolated from wild rice (Oryza rufipogon) in China. In this study, we demonstrate that a number of clinical isolates that were either described in the literature, preserved in culture collections, or obtained during a 2013 multi-state sepsis outbreak in Brazil also belong to the same genus. 16S rRNA gene sequencing, multilocus sequence analysis based on gyrB, rpoB, atpD and infB genes, as well as digital DNA-DNA hybridization support the existence of a second species within the genus Phytobacter. All isolates from the recent Brazilian outbreak, along with some older American clinical strains, were found to belong to the already described species Phytobacterdiazotrophicus, whereas three clinical strains retrieved in the USA over a time span of almost four decades, could be assigned to a new Phytobacter species. Implementation of an extended set of biochemical tests showed that the two Phytobacter species could phenotypically be discriminated from each other by the ability to utilize l-sorbose and d-serine. This feature was limited to the strains of the novel species described herein, for which the name Phytobacter ursingii sp. nov. is proposed, with ATCC 27989T (=CNCTC 5729T) as the designated type strain. An emended description of the species Phytobacter diazotrophicus and of the genus Phytobacter is also provided.

Role of peripheral blood minimum residual disease at day 8 of induction therapy in high-risk pediatric patients with acute lymphocytic leukemia.

Risk stratification and treatment intensification, based on minimal residual disease (MRD) mensurement, changed the prognosis of pediatric patients with acute lymphocytic leukemia (ALL). The main aim of this study was to investigate whether peripheral blood (PB) MRD measurement at day 8 (D8) could predict the risk stratification category determined by bone marrow (BM) MRD at day 15 (D15). The study was performed prospectively, in a cohort of 40 children with B-lineage ALL, adopting the protocol of the Brazilian Cooperative Group of the Treatment Childhood Leukemia (GBTLI-2009). MRD was detected by flow cytometry (FC) using a simplifed panel that can reliably identify MRD at early phases of induction therapy. Upon diagnosis, the proportion of low and high-risk patients, was 24:16 (60%:40%). The main result of our study demonstrated the potential of D8 MRD in anticipating of week the risk stratification of high-risk patients as determined by D15 BM MRD. In these patients D8 MRD level of 1% was able to segregate high risk fast responders from high risk slow responders (p = 0.0097). This result could represent an opportunity for early treatment intensification, as already performed in some protocols.

Association Analysis Suggests SOD2 as a Newly Identified Candidate Gene Associated With Leprosy Susceptibility.

Genetic studies have identified several genes and genomic regions contributing to the control of host susceptibility to leprosy. Here, we test variants of the positional and functional candidate gene SOD2 for association with leprosy in 2 independent population samples. Family-based analysis revealed an association between leprosy and allele G of marker rs295340 (P = .042) and borderline evidence of an association between leprosy and alleles C and A of markers rs4880 (P = .077) and rs5746136 (P = .071), respectively. Findings were validated in an independent case-control sample for markers rs295340 (P = .049) and rs4880 (P = .038). These results suggest SOD2 as a newly identified gene conferring susceptibility to leprosy.