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BACKGROUND: Total serum IgE (tIgE) is an important intermediate phenotype of allergic disease. Whole genome genetic association studies across ancestries may identify important determinants of IgE. OBJECTIVE: We aimed to increase understanding of genetic variants affecting tIgE production across the ancestry and allergic disease spectrum by leveraging data from the National Heart, Lung and Blood Institute Trans-Omics for Precision Medicine program; the Consortium on Asthma among African-ancestry Populations in the Americas (CAAPA); and the Atopic Dermatitis Research Network (N = 21,901). METHODS: We performed genome-wide association within strata of study, disease, and ancestry groups, and we combined results via a meta-regression approach that models heterogeneity attributable to ancestry. We also tested for association between HLA alleles called from whole genome sequence data and tIgE, assessing replication of associations in HLA alleles called from genotype array data. RESULTS: We identified 6 loci at genome-wide significance (P < 5 × 10-9), including 4 loci previously reported as genome-wide significant for tIgE, as well as new regions in chr11q13.5 and chr15q22.2, which were also identified in prior genome-wide association studies of atopic dermatitis and asthma. In the HLA allele association study, HLA-A∗02:01 was associated with decreased tIgE level (Pdiscovery = 2 × 10-4; Preplication = 5 × 10-4; Pdiscovery+replication = 4 × 10-7), and HLA-DQB1∗03:02 was strongly associated with decreased tIgE level in Hispanic/Latino ancestry populations (PHispanic/Latino discovery+replication = 8 × 10-8). CONCLUSION: We performed the largest genome-wide association study and HLA association study of tIgE focused on ancestrally diverse populations and found several known tIgE and allergic disease loci that are relevant in non-European ancestry populations.
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Asma/genética , Dermatite Atópica/genética , Etnicidade , Genótipo , Antígeno HLA-A2/genética , Cadeias beta de HLA-DQ/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , National Heart, Lung, and Blood Institute (U.S.) , Estados Unidos , Sequenciamento Completo do Genoma , Adulto JovemRESUMO
MOTIVATION: The HLA system plays a pivotal role in both clinical applications and immunology research. Typing HLA genes in patient and donor is indeed required in hematopoietic stem cell and solid-organ transplantation, and the histocompatibility complex region exhibits countless genetic associations with immune-related pathologies. Since the discovery of HLA antigens, the HLA system nomenclature and typing methods have constantly evolved, which leads to difficulties in using data generated with older methodologies. RESULTS: Here, we present Easy-HLA, a web-based software suite designed to facilitate analysis and gain knowledge from HLA typing, regardless of nomenclature or typing method. Easy-HLA implements a computational and statistical method of HLA haplotypes inference based on published reference populations containing over 600 000 haplotypes to upgrade missing or partial HLA information: 'HLA-Upgrade' tool infers high-resolution HLA typing and 'HLA-2-Haplo' imputes haplotype pairs and provides additional functional annotations (e.g. amino acids and KIR ligands). We validated both tools using two independent cohorts (total n = 2500). For HLA-Upgrade, we reached a prediction accuracy of 92% from low- to high-resolution of European genotypes. We observed a 96% call rate and 76% accuracy with HLA-2-Haplo European haplotype pairs prediction. In conclusion, Easy-HLA tools facilitate large-scale immunogenetic analysis and promotes the multi-faceted HLA expertise beyond allelic associations by providing new functional immunogenomics parameters. AVAILABILITY AND IMPLEMENTATION: Easy-HLA is a web application freely available (free account) at: https://hla.univ-nantes.fr. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Antígenos HLA , Alelos , Genótipo , Haplótipos , Teste de Histocompatibilidade , HumanosRESUMO
BACKGROUND: Asthma is a complex chronic inflammatory disease of the airways. Association studies between HLA and asthma were first reported in the 1970s, and yet, the precise role of HLA alleles in asthma is not fully understood. Numerous genome-wide association studies were recently conducted on asthma, but were always limited to simple genetic markers (single nucleotide polymorphisms) and not complex HLA gene polymorphisms (alleles/haplotypes), therefore not capturing the biological relevance of this complex locus for asthma pathogenesis. OBJECTIVE: To run the first HLA-centric association study with asthma and specific asthma-related phenotypes in a large cohort of African-ancestry individuals. METHODS: We collected high-density genomics data for the Consortium on Asthma among African-ancestry Populations in the Americas (N = 4993) participants. Using computer-intensive machine-learning attribute bagging methods to infer HLA alleles, and Easy-HLA to infer HLA 5-gene haplotypes, we conducted a high-throughput HLA-centric association study of asthma susceptibility and total serum IgE (tIgE) levels in subjects with and without asthma. RESULTS: Among the 1607 individuals with asthma, 972 had available tIgE levels, with a mean tIgE level of 198.7 IU/mL. We could not identify any association with asthma susceptibility. However, we showed that HLA-DRB1∗09:01 was associated with increased tIgE levels (P = 8.5 × 10-4; weighted effect size, 0.51 [0.15-0.87]). CONCLUSIONS: We identified for the first time an HLA allele associated with tIgE levels in African-ancestry individuals with asthma. Our report emphasizes that by leveraging powerful computational machine-learning methods, specific/extreme phenotypes, and population diversity, we can explore HLA gene polymorphisms in depth and reveal the full extent of complex disease associations.
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Alelos , Negro ou Afro-Americano/genética , Cadeias HLA-DRB1/genética , Imunoglobulina E/imunologia , Polimorfismo de Nucleotídeo Único , Asma , Feminino , Cadeias HLA-DRB1/imunologia , Humanos , MasculinoRESUMO
Characterization of genetic admixture of populations in the Americas and the Caribbean is of interest for anthropological, epidemiological, and historical reasons. Asthma has a higher prevalence and is more severe in populations with a high African component. Association of African ancestry with asthma has been demonstrated. We estimated admixture proportions of samples from six trihybrid populations of African descent and determined the relationship between African ancestry and asthma and total serum IgE levels (tIgE). We genotyped 237 ancestry informative markers in asthmatics and nonasthmatic controls from Barbados (190/277), Jamaica (177/529), Brazil (40/220), Colombia (508/625), African Americans from New York (207/171), and African Americans from Baltimore/Washington, D.C. (625/757). We estimated individual ancestries and evaluated genetic stratification using Structure and principal component analysis. Association of African ancestry and asthma and tIgE was evaluated by regression analysis. Mean ± SD African ancestry ranged from 0.76 ± 0.10 among Barbadians to 0.33 ± 0.13 in Colombians. The European component varied from 0.14 ± 0.05 among Jamaicans and Barbadians to 0.26 ± 0.08 among Colombians. African ancestry was associated with risk for asthma in Colombians (odds ratio (OR) = 4.5, P = 0.001) Brazilians (OR = 136.5, P = 0.003), and African Americans of New York (OR: 4.7; P = 0.040). African ancestry was also associated with higher tIgE levels among Colombians (ß = 1.3, P = 0.04), Barbadians (ß = 3.8, P = 0.03), and Brazilians (ß = 1.6, P = 0.03). Our findings indicate that African ancestry can account for, at least in part, the association between asthma and its associated trait, tIgE levels.
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Asma/etnologia , Asma/genética , População Negra/genética , Imunoglobulina E/genética , Negro ou Afro-Americano/genética , Algoritmos , Asma/epidemiologia , Barbados , Brasil , Estudos de Casos e Controles , Colômbia , District of Columbia , Predisposição Genética para Doença , Humanos , Imunoglobulina E/sangue , Jamaica , Modelos Estatísticos , Epidemiologia Molecular , New York , Fatores de Risco , População Branca/genéticaRESUMO
Asthma has striking disparities across ancestral groups, but the molecular underpinning of these differences is poorly understood and minimally studied. A goal of the Consortium on Asthma among African-ancestry Populations in the Americas (CAAPA) is to understand multi-omic signatures of asthma focusing on populations of African ancestry. RNASeq and DNA methylation data are generated from nasal epithelium including cases (current asthma, N = 253) and controls (never-asthma, N = 283) from 7 different geographic sites to identify differentially expressed genes (DEGs) and gene networks. We identify 389 DEGs; the top DEG, FN1, was downregulated in cases (q = 3.26 × 10-9) and encodes fibronectin which plays a role in wound healing. The top three gene expression modules implicate networks related to immune response (CEACAM5; p = 9.62 × 10-16 and CPA3; p = 2.39 × 10-14) and wound healing (FN1; p = 7.63 × 10-9). Multi-omic analysis identifies FKBP5, a co-chaperone of glucocorticoid receptor signaling known to be involved in drug response in asthma, where the association between nasal epithelium gene expression is likely regulated by methylation and is associated with increased use of inhaled corticosteroids. This work reveals molecular dysregulation on three axes - increased Th2 inflammation, decreased capacity for wound healing, and impaired drug response - that may play a critical role in asthma within the African Diaspora.
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Asma , População Negra , Metilação de DNA , Mucosa Nasal , Proteínas de Ligação a Tacrolimo , Humanos , Asma/genética , Asma/metabolismo , Mucosa Nasal/metabolismo , Proteínas de Ligação a Tacrolimo/genética , Proteínas de Ligação a Tacrolimo/metabolismo , Feminino , Masculino , População Negra/genética , Adulto , Redes Reguladoras de Genes , Fibronectinas/metabolismo , Fibronectinas/genética , Estudos de Casos e Controles , Regulação da Expressão Gênica , Pessoa de Meia-Idade , MultiômicaRESUMO
Background: Burnout is common among doctors working in emergency departments. It has significant consequences and is multifactorial. Self-care and resilience tendencies may contribute to being burnt out, or not. This study explores burnout and resilience amongst physicians working in Caribbean emergency departments. Methods: Data were collected from 111 participants using the Maslach Burnout Inventory (MBI) and the Resilience Scale-14 (RS14) as measures of burnout and resilience, respectively. Questions collected data on participant demographics and characteristics related to self-care. The associations between demographic characteristics and total burnout and resilience scales were explored. Findings: Among participants, 88.6% had medium to high range emotional exhaustion, 82.8% exhibited medium to high range depersonalization, and 19.6% had low to medium range personal accomplishment. Participants in Barbados had higher emotional exhaustion and depersonalization scores (p=0.009), and those in a postgraduate programme had higher depersonalization scores (p=0.047). The mean RS-14 score was 81.1 out of a maximum of 98.0 with a standard deviation of 13.1 and a range of 26 to 98. Depression correlated with high emotional exhaustion scores (p=0.004) and low resilience scores (p<0.0001). Emotional exhaustion scores increased among participants using alcohol daily (p=0.01), using recreational drugs (p=0.021) and sleeping aids (p=0.028). Interpretation: High burnout, despite high resilience, is present in this sample of physicians working in emergency departments of teaching hospitals in the Caribbean. Although resilience scores were high, those with lower resilience tendencies had poorer self-care habits. Funding: No external funding.
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Admixture is a potential source of confounding in genetic association studies, so it becomes important to detect and estimate admixture in a sample of unrelated individuals. Populations of African descent in the US and the Caribbean share similar historical backgrounds but the distributions of African admixture may differ. We selected 416 ancestry informative markers (AIMs) to estimate and compare admixture proportions using STRUCTURE in 906 unrelated African Americans (AAs) and 294 Barbadians (ACs) from a study of asthma. This analysis showed AAs on average were 72.5% African, 19.6% European and 8% Asian, while ACs were 77.4% African, 15.9% European, and 6.7% Asian which were significantly different. A principal components analysis based on these AIMs yielded one primary eigenvector that explained 54.04% of the variation and captured a gradient from West African to European admixture. This principal component was highly correlated with African vs. European ancestry as estimated by STRUCTURE (r(2)=0.992, r(2)=0.912, respectively). To investigate other African contributions to African American and Barbadian admixture, we performed PCA on approximately 14,000 (14k) genome-wide SNPs in AAs, ACs, Yorubans, Luhya and Maasai African groups, and estimated genetic distances (F(ST)). We found AAs and ACs were closest genetically (F(ST)=0.008), and both were closer to the Yorubans than the other East African populations. In our sample of individuals of African descent, approximately 400 well-defined AIMs were just as good for detecting substructure as approximately 14,000 random SNPs drawn from a genome-wide panel of markers.
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População Negra/genética , Negro ou Afro-Americano/genética , População Branca/genética , Algoritmos , Barbados/epidemiologia , Região do Caribe/epidemiologia , Estudos de Casos e Controles , Frequência do Gene , Genética Populacional , Genótipo , Haplótipos , Humanos , Cadeias de Markov , Polimorfismo de Nucleotídeo Único , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: Asthma is a complex disease characterized by striking ethnic disparities not explained entirely by environmental, social, cultural, or economic factors. Of the limited genetic studies performed on populations of African descent, notable differences in susceptibility allele frequencies have been observed. OBJECTIVES: We sought to test the hypothesis that some genes might contribute to the profound disparities in asthma. METHODS: We performed a genome-wide association study in 2 independent populations of African ancestry (935 African American asthmatic cases and control subjects from the Baltimore-Washington, DC, area and 929 African Caribbean asthmatic subjects and their family members from Barbados) to identify single-nucleotide polymorphisms (SNPs) associated with asthma. RESULTS: A meta-analysis combining these 2 African-ancestry populations yielded 3 SNPs with a combined P value of less than 10(-5) in genes of potential biologic relevance to asthma and allergic disease: rs10515807, mapping to the alpha-1B-adrenergic receptor (ADRA1B) gene on chromosome 5q33 (3.57 x 10(-6)); rs6052761, mapping to the prion-related protein (PRNP) gene on chromosome 20pter-p12 (2.27 x 10(-6)); and rs1435879, mapping to the dipeptidyl peptidase 10 (DPP10) gene on chromosome 2q12.3-q14.2. The generalizability of these findings was tested in family and case-control panels of United Kingdom and German origin, respectively, but none of the associations observed in the African groups were replicated in these European studies. Evidence for association was also examined in 4 additional case-control studies of African Americans; however, none of the SNPs implicated in the discovery population were replicated. CONCLUSIONS: This study illustrates the complexity of identifying true associations for a complex and heterogeneous disease, such as asthma, in admixed populations, especially populations of African descent.
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Asma/genética , População Negra/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Adulto , Negro ou Afro-Americano/genética , Barbados , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo ÚnicoRESUMO
RATIONALE: Asthma prevalence and severity are high among underserved minorities, including those of African descent. The Duffy antigen/receptor for chemokines is the receptor for Plasmodium vivax on erythrocytes and functions as a chemokine-clearing receptor. Unlike European populations, decreased expression of the receptor on erythrocytes is common among populations of African descent, and results from a functional T-46C polymorphism (rs2814778) in the promoter. This variant provides an evolutionary advantage in malaria-endemic regions, because Duffy antigen/receptor for chemokines-negative erythrocytes are more resistant to infection by P. vivax. OBJECTIVES: To determine the role of the rs2814778 polymorphism in asthma and atopy as measured by total serum IgE levels among four populations of African descent (African Caribbean, African American, Brazilian, and Colombian) and a European American population. METHODS: Family-based association tests were performed in each of the five populations to test for association between the rs2814778 polymorphism and asthma or total IgE concentration. MEASUREMENTS AND MAIN RESULTS: Asthma was significantly associated with the rs2814778 polymorphism in the African Caribbean, Colombian, and Brazilian families (P < 0.05). High total IgE levels were associated with this variant in African Caribbean and Colombian families (P < 0.05). The variant allele was not polymorphic among European Americans. CONCLUSIONS: Susceptibility to asthma and atopy among certain populations of African descent is influenced by a functional polymorphism in the gene encoding Duffy antigen/receptor for chemokines. This genetic variant, which confers resistance to malarial parasitic infection, may also partially explain ethnic differences in morbidity of asthma.
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Asma/genética , População Negra/genética , Sistema do Grupo Sanguíneo Duffy/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores de Superfície Celular/genética , Adolescente , Adulto , Barbados , Brasil , Estudos de Casos e Controles , Colômbia , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Estados Unidos , População Branca/genéticaRESUMO
Anti-glomerular basement membrane (anti-GBM) glomerulonephritis is a rare disease caused by autoantibodies against the glomerular basement membrane. Atypical anti-GBM nephritis is clinically less aggressive and characterized by the absence of circulating autoantibodies to the basement membrane. A previously healthy 53-year-old white woman presented with a rising creatinine over a short observation period. Renal biopsy, urinary sediment, and laboratory testing confirmed the diagnosis of atypical anti-GBM disease. She received plasmapheresis, steroids, and cyclophosphamide. She developed hemorrhagic cystitis early in the treatment from oral cyclophosphamide and mycophenolate mofetil was substituted as a first-line drug. She responded favorably and continued on mycophenolate mofetil without evidence of relapse. Despite the absence of circulating autoantibodies, a diagnosis of atypical anti-GBM nephritis should not be excluded if a high index of clinical suspicion exists. Early renal biopsy should be considered. Mycophenolate mofetil may be a reasonable replacement for oral cyclophosphamide in the treatment of atypical anti-GBM disease when cyclophosphamide is contraindicated.
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In the version of this article initially published, the statement "there are no pan-genomes for any other animal or plant species" was incorrect. The statement has been corrected to "there are no reported pan-genomes for any other animal species, to our knowledge." We thank David Edwards for bringing this error to our attention. The error has been corrected in the HTML and PDF versions of the article.
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We used a deeply sequenced dataset of 910 individuals, all of African descent, to construct a set of DNA sequences that is present in these individuals but missing from the reference human genome. We aligned 1.19 trillion reads from the 910 individuals to the reference genome (GRCh38), collected all reads that failed to align, and assembled these reads into contiguous sequences (contigs). We then compared all contigs to one another to identify a set of unique sequences representing regions of the African pan-genome missing from the reference genome. Our analysis revealed 296,485,284 bp in 125,715 distinct contigs present in the populations of African descent, demonstrating that the African pan-genome contains ~10% more DNA than the current human reference genome. Although the functional significance of nearly all of this sequence is unknown, 387 of the novel contigs fall within 315 distinct protein-coding genes, and the rest appear to be intergenic.
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População Negra/genética , Genoma Humano/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Análise de Sequência de DNA/métodosRESUMO
Type B lactic acidosis is a rare metabolic complication sometimes associated with hematologic malignancies. When present, this type of lactic acidosis is most commonly seen in patients with high-grade lymphomas or leukemias and is usually indicative of a dismal prognosis. We report a case of a 27-year man with acquired immunodeficiency syndrome (AIDS) that presented with bilateral lower extremity swelling, an abdominal mass, and weight loss. His lab values showed elevated anion gap with lactic acidosis and computed tomography (CT) of the abdomen showed a large soft-tissue mass arising from the left hepatic lobe. Biopsy of the abdominal mass demonstrated a high-grade diffuse large B-cell lymphoma. The patient's lactic acidosis resolved after starting chemotherapy, and a complete response was evident on PET-CT after a third cycle of rituximab, etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin (EPOC-RR). Care-givers should be aware of the implications of lactic acidosis associated with malignancy and the need for prompt diagnosis and treatment.
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Bullous pemphigoid is the most common of the blistering disorders. It is most commonly found in the elderly and is diagnosed based on clinical, histologic, and immunologic criteria. It presents clinically with diffuse eczematous, pruritic, urticaria-like lesions, with the later appearance of tense bullae or blistering lesions typically filled with clear fluid. Histologically, a sub-epidermal blister is seen and immunofluorescence shows immunoglobulin G antibodies directed against the structural components of the keratinocytic hemidesmosomal proteins BP180 and BP230. Multiple treatment modalities are present for this condition, including anti-inflammatory medications, medications that reduce antibody formation, and treatments to increase the elimination of antibodies. The aim of this case report is to present a classic case of this condition, to highlight an awareness of differing treatment options, and to advocate referral to a dermatologist given its potential severity.
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: Congenital deficiency of factor II is a very rare autosomal recessive disorder that can result in a bleeding diathesis. Genotypically, individuals are either homozygous for a defective prothrombin gene or a compound heterozygote with different mutated prothrombin genes inherited from each parent. Phenotypically, it is characterized by either a low production of normal prothrombin or a near-normal production of dysfunctional prothrombin. Treatment is aimed at restoring normally functioning factor II circulating levels to sufficient concentration for hemostasis. Paradoxical thrombosis in patients born from a nonconsanguineous marriage with factor II deficiency has not been reported. A woman with known congenital factor II deficiency confirmed by history and hemostatic laboratory analysis presented with an unprovoked spontaneous thrombosis of the common femoral vein detected on color Doppler. Venous thrombosis can occur in congenital deficiency of factor II and inferior vena cava filter can be life-saving.
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Testes de Coagulação Sanguínea/métodos , Hipoprotrombinemias/genética , Trombofilia/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Trombofilia/genéticaRESUMO
The African Diaspora in the Western Hemisphere represents one of the largest forced migrations in history and had a profound impact on genetic diversity in modern populations. To date, the fine-scale population structure of descendants of the African Diaspora remains largely uncharacterized. Here we present genetic variation from deeply sequenced genomes of 642 individuals from North and South American, Caribbean and West African populations, substantially increasing the lexicon of human genomic variation and suggesting much variation remains to be discovered in African-admixed populations in the Americas. We summarize genetic variation in these populations, quantifying the postcolonial sex-biased European gene flow across multiple regions. Moreover, we refine estimates on the burden of deleterious variants carried across populations and how this varies with African ancestry. Our data are an important resource for empowering disease mapping studies in African-admixed individuals and will facilitate gene discovery for diseases disproportionately affecting individuals of African ancestry.
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População Negra/genética , Fluxo Gênico , Genoma Humano , Migração Humana , Sequência de Bases , DNA Intergênico/genética , Feminino , Heterogeneidade Genética , Geografia , Humanos , Masculino , Filogenia , Polimorfismo de Nucleotídeo Único/genética , SexismoRESUMO
Asthma is a common disease with a complex risk architecture including both genetic and environmental factors. We performed a meta-analysis of North American genome-wide association studies of asthma in 5,416 individuals with asthma (cases) including individuals of European American, African American or African Caribbean, and Latino ancestry, with replication in an additional 12,649 individuals from the same ethnic groups. We identified five susceptibility loci. Four were at previously reported loci on 17q21, near IL1RL1, TSLP and IL33, but we report for the first time, to our knowledge, that these loci are associated with asthma risk in three ethnic groups. In addition, we identified a new asthma susceptibility locus at PYHIN1, with the association being specific to individuals of African descent (P = 3.9 × 10(-9)). These results suggest that some asthma susceptibility loci are robust to differences in ancestry when sufficiently large samples sizes are investigated, and that ancestry-specific associations also contribute to the complex genetic architecture of asthma.
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Asma/etnologia , Asma/genética , Loci Gênicos , Predisposição Genética para Doença , Negro ou Afro-Americano/genética , Asma/epidemiologia , Região do Caribe/etnologia , Estudo de Associação Genômica Ampla , Hispânico ou Latino/genética , Humanos , América do Norte/etnologia , Risco , População Branca/genéticaRESUMO
The management of pelvic fractures and hip injuries requires a multidisciplinary approach and begins in the prehospital setting. With the current advances in various investigative modalities along with the use of algorithms, the morbidity and mortality from these injuries has improved. This review discusses an outline of the current recommendations along with treatment strategies and options in the emergency department, which may vary from institution to institution based on the availability of expertise and resources and because no two trauma patients are alike with regard to the pathophysiology and injury patterns.
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Fraturas Ósseas/diagnóstico , Lesões do Quadril/diagnóstico , Procedimentos Ortopédicos/métodos , Ossos Pélvicos/lesões , Fraturas Ósseas/terapia , Lesões do Quadril/terapia , HumanosRESUMO
BACKGROUND: Myosin light chain kinase (MYLK) is a multifunctional protein involved in regulation of airway hyperreactivity and other activities relevant to asthma. OBJECTIVE: To determine the role of MYLK gene variants in asthma among African Caribbean and African American populations. METHODS: We performed association tests between single nucleotide polymorphisms (SNPs) in the MYLK gene and asthma susceptibility and total serum IgE concentrations in 2 independent, family-based populations of African descent. Previously we identified variants/haplotypes in MYLK that confer risk for sepsis and acute lung injury; we compared findings from our asthma populations to findings in the African American sepsis and acute lung injury groups. RESULTS: Significant associations between MYLK SNPs and asthma and total serum IgE concentrations were observed in the African Caribbean families: a promoter SNP (rs936170) in the smooth muscle form gave the strongest association (P = .009). A haplotype including rs936170 corresponding to the actin-binding activity of the nonmuscle and smooth muscle forms was negatively associated with asthma (eg, decreased risk) in both the American (P = .005) and Caribbean families (P = .004), and was the same haplotype that conferred risk for severe sepsis (P = .002). RNA expression studies on PBMCs and rs936170 suggested a significant decrease in MYLK expression among patients with asthma with this variant (P = .025). CONCLUSION: MYLK polymorphisms may function as a common genetic factor in clinically distinct diseases involving bronchial smooth muscle contraction and inflammation. CLINICAL IMPLICATIONS: Genetic variants in MYLK are significantly associated with both asthma and sepsis in populations of African ancestry.
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Asma/genética , Predisposição Genética para Doença , Quinase de Cadeia Leve de Miosina/genética , Sepse/genética , Negro ou Afro-Americano/genética , População Negra/genética , Região do Caribe , Feminino , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Fatores de RiscoRESUMO
Nystatin is an antifungal compound with potent proinflammatory properties. Herein, we demonstrate that nystatin induces interleukin (IL)-1beta, IL-8, and tumor necrosis factor alpha secretion through its activation of toll-like receptor 1 (TLR1) and TLR2. Hence, a TLR-dependent mechanism could serve as the molecular basis for the proinflammatory properties of nystatin.