The Virtual Child.

SUMMARY: We are building the world's first Virtual Child-a computer model of normal and cancerous human development at the level of each individual cell. The Virtual Child will "develop cancer" that we will subject to unlimited virtual clinical trials that pinpoint, predict, and prioritize potential new treatments, bringing forward the day when no child dies of cancer, giving each one the opportunity to lead a full and healthy life.

Interleukin-3 production by basal-like breast cancer cells is associated with poor prognosis.

Breast cancer represents a collection of pathologies with different molecular subtypes, histopathology, risk factors, clinical behavior, and responses to treatment. "Basal-like" breast cancers predominantly lack the receptors for estrogen and progesterone (ER/PR), lack amplification of human epidermal growth factor receptor 2 (HER2) but account for 10-15% of all breast cancers, are largely insensitive to targeted treatment and represent a disproportionate number of metastatic cases and deaths. Analysis of interleukin (IL)-3 and the IL-3 receptor subunits (IL-3RA + CSF2RB) reveals elevated expression in predominantly the basal-like group. Further analysis suggests that IL-3 itself, but not the IL-3 receptor subunits, associates with poor patient outcome. Histology on patient-derived xenografts supports the notion that breast cancer cells are a significant source of IL-3 that may promote disease progression. Taken together, these observations suggest that IL-3 may be a useful marker in solid tumors, particularly triple negative breast cancer, and warrants further investigation into its contribution to disease pathogenesis.

Pre-clinical validation of a pan-cancer CAR-T cell immunotherapy targeting nfP2X7.

Chimeric antigen receptor (CAR)-T cell immunotherapy is a novel treatment that genetically modifies the patients' own T cells to target and kill malignant cells. However, identification of tumour-specific antigens expressed on multiple solid cancer types, remains a major challenge. P2X purinoceptor 7 (P2X7) is a cell surface expressed ATP gated cation channel, and a dysfunctional version of P2X7, named nfP2X7, has been identified on cancer cells from multiple tissues, while being undetectable on healthy cells. We present a prototype -human CAR-T construct targeting nfP2X7 showing potential antigen-specific cytotoxicity against twelve solid cancer types (breast, prostate, lung, colorectal, brain and skin). In xenograft mouse models of breast and prostate cancer, CAR-T cells targeting nfP2X7 exhibit robust anti-tumour efficacy. These data indicate that nfP2X7 is a suitable immunotherapy target because of its broad expression on human tumours. CAR-T cells targeting nfP2X7 have potential as a wide-spectrum cancer immunotherapy for solid tumours in humans.

Menstrual Suppression in the Myelosuppressed: A Retrospective Cohort Study.

PURPOSE: Adolescent and young adult female patients receiving myelosuppressive cancer treatments are at risk of abnormal uterine bleeding (AUB). The frequency with which patients with cancer receive menstrual suppression and the agents used have not previously been well-characterized. We studied the rate of menstrual suppression, the effect of suppression on bleeding and blood product utilization, and if there were practice pattern differences between adult and pediatric oncologists. METHODS: We established a retrospective cohort of 90 females with a diagnosis of Hodgkin or non-Hodgkin lymphoma (n = 25), AML (n = 46), or sarcoma (n = 19) and treated with chemotherapy between 2008 and 2019 at our institutions (University of Alabama at Birmingham [UAB] adult oncology: UAB hospital; UAB pediatric oncology: Children's of Alabama). Data were abstracted from the medical record including sociodemographics, primary oncologist specialty (pediatric v adult), cancer details (diagnosis and treatment) and gynecologic course (documented gynecologic history, menstrual suppression agents used, reported AUB outcomes, and treatments). RESULTS: The majority of patients (77.8%) received menstrual suppression. Compared with nonsuppressed patients, suppressed patients had similar rates of packed red blood cell transfusions but higher number of platelet transfusions. Adult oncologists were more likely to document a gynecologic history, consult gynecology, and list AUB as a problem. Among suppressed patients, there was heterogeneity in the agents used for menstrual suppression, with a predilection toward progesterone-only agents; a low rate of thrombotic events was observed. CONCLUSION: Menstrual suppression was common in our cohort with variability in agents used. Pediatric and adult oncologists demonstrated different practice patterns.

The dinitrobenzamide mustard prodrugs, PR-104A and SN27686, for use in a novel MNDEPT cancer prodrug therapy approach.

Directed enzyme prodrug therapy is a highly promising anti-cancer strategy. However, the current technology is limited by inefficient prodrug activation and the dose-limiting toxicity associated with the prodrugs being tested; to overcome these limitations, the dinitrobenzamide mustard prodrugs, PR-104A and SN27686, have been developed. The present study will assess both of these prodrugs for their potential uses in a novel magnetic-nanoparticle directed enzyme prodrug therapy strategy by determining their kinetic parameters, assessing the products formed during enzymatic reduction using HPLC and finally their ability to cause cell death in the ovarian cancer cell line, SK-OV-3. It was shown for the first time that the dinitrobenzamide mustard prodrugs are able to be reduced by the genetically modified nitroreductases, NfnB-cys and YfkO-cys, and that these enzyme/prodrug combinations can induce a significant cell death in the SK-OV-3 cell line, highlighting the potential for both enzyme/prodrug combinations for use in magnetic-nanoparticle directed enzyme prodrug therapy.

Multi-omic association study identifies DNA methylation-mediated genotype and smoking exposure effects on lung function in children living in urban settings.

Impaired lung function in early life is associated with the subsequent development of chronic respiratory disease. Most genetic associations with lung function have been identified in adults of European descent and therefore may not represent those most relevant to pediatric populations and populations of different ancestries. In this study, we performed genome-wide association analyses of lung function in a multiethnic cohort of children (n = 1,035) living in low-income urban neighborhoods. We identified one novel locus at the TDRD9 gene in chromosome 14q32.33 associated with percent predicted forced expiratory volume in one second (FEV1) (p = 2.4x10-9; ßz = -0.31, 95% CI = -0.41- -0.21). Mendelian randomization and mediation analyses revealed that this genetic effect on FEV1 was partially mediated by DNA methylation levels at this locus in airway epithelial cells, which were also associated with environmental tobacco smoke exposure (p = 0.015). Promoter-enhancer interactions in airway epithelial cells revealed chromatin interaction loops between FEV1-associated variants in TDRD9 and the promoter region of the PPP1R13B gene, a stimulator of p53-mediated apoptosis. Expression of PPP1R13B in airway epithelial cells was significantly associated the FEV1 risk alleles (p = 1.3x10-5; ß = 0.12, 95% CI = 0.06-0.17). These combined results highlight a potential novel mechanism for reduced lung function in urban youth resulting from both genetics and smoking exposure.

Insights to the Structural Basis for the Stereospecificity of the Escherichia coli Phytase, AppA.

AppA, the Escherichia coli periplasmic phytase of clade 2 of the histidine phosphatase (HP2) family, has been well-characterized and successfully engineered for use as an animal feed supplement. AppA is a 1D-6-phytase and highly stereospecific but transiently accumulates 1D-myo-Ins(2,3,4,5)P4 and other lower phosphorylated intermediates. If this bottleneck in liberation of orthophosphate is to be obviated through protein engineering, an explanation of its rather rigid preference for the initial site and subsequent cleavage of phytic acid is required. To help explain this behaviour, the role of the catalytic proton donor residue in determining AppA stereospecificity was investigated. Four variants were generated by site-directed mutagenesis of the active site HDT amino acid sequence motif containing the catalytic proton donor, D304. The identity and position of the prospective proton donor residue was found to strongly influence stereospecificity. While the wild-type enzyme has a strong preference for 1D-6-phytase activity, a marked reduction in stereospecificity was observed for a D304E variant, while a proton donor-less mutant (D304A) displayed exclusive 1D-1/3-phytase activity. High-resolution X-ray crystal structures of complexes of the mutants with a non-hydrolysable substrate analogue inhibitor point to a crucial role played by D304 in stereospecificity by influencing the size and polarity of specificity pockets A and B. Taken together, these results provide the first evidence for the involvement of the proton donor residue in determining the stereospecificity of HP2 phytases and prepares the ground for structure-informed engineering studies targeting the production of animal feed enzymes capable of the efficient and complete dephosphorylation of dietary phytic acid.

The future of orthopaedic surgical education: Where do we go now?

INTRODUCTION: COVID-19 will undoubtedly change the future landscape of medical and surgical education. The economic and environmental advantages of virtual learning are clear, while access to a wider range of resources and subject specialists makes the adoption of virtual learning within surgical education an attractive prospect. AIMS: This literature review aims to evaluate evidence on the effectiveness of virtual education in orthopaedics and how we might implement positive changes to educational practice in the future, as a result of lessons learned during the COVID-19 pandemic. METHODOLOGY: We performed a review of the literature reporting on efficacy of learning outcomes achieved as a result of virtual education within orthopaedic surgery. Electronic searches were performed using NICE healthcare databases from the date of inception to March 2021. Relevant studies were identified, data extracted, and qualitative synthesis performed. RESULTS: 14 manuscripts with a total of 1548 participants (orthopaedic trainees or medical students) were included for analysis. Nine studies (n = 1109) selected compared e-learning to conventional learning material (control group). All nine studies reported significantly higher outcome scores for e-learning participants compared to control participants (p < 0.001 to p < 0.05). The remaining studies compared blended e-learning approaches or evaluated pre/post intervention improvements in learning outcomes. All studies demonstrated a significant improvement in learning outcomes (p < 0.0001 to p < 0.01). The majority of studies (64%) used a blended approach. No studies were identified reporting efficacy of webinars or videoconferencing within orthopaedic education. CONCLUSION: A blended approach, combining virtual teaching, face-to-face instruction and distance learning tools, based on the evidence we have provided, would improve the quality of knowledge reception and retention, and learner satisfaction. However, in order to be successful, it is vital that these educational programmes are designed with the needs of the learner in mind, and an awareness of best practice for virtual teaching and learning.

Multi-omics colocalization with genome-wide association studies reveals a context-specific genetic mechanism at a childhood onset asthma risk locus.

BACKGROUND: Genome-wide association studies (GWASs) have identified thousands of variants associated with asthma and other complex diseases. However, the functional effects of most of these variants are unknown. Moreover, GWASs do not provide context-specific information on cell types or environmental factors that affect specific disease risks and outcomes. To address these limitations, we used an upper airway epithelial cell (AEC) culture model to assess transcriptional and epigenetic responses to rhinovirus (RV), an asthma-promoting pathogen, and provide context-specific functional annotations to variants discovered in GWASs of asthma. METHODS: Genome-wide genetic, gene expression, and DNA methylation data in vehicle- and RV-treated upper AECs were collected from 104 individuals who had a diagnosis of airway disease (n=66) or were healthy participants (n=38). We mapped cis expression and methylation quantitative trait loci (cis-eQTLs and cis-meQTLs, respectively) in each treatment condition (RV and vehicle) in AECs from these individuals. A Bayesian test for colocalization between AEC molecular QTLs and adult onset asthma and childhood onset asthma GWAS SNPs, and a multi-ethnic GWAS of asthma, was used to assign the function to variants associated with asthma. We used Mendelian randomization to demonstrate DNA methylation effects on gene expression at asthma colocalized loci. RESULTS: Asthma and allergic disease-associated GWAS SNPs were specifically enriched among molecular QTLs in AECs, but not in GWASs from non-immune diseases, and in AEC eQTLs, but not among eQTLs from other tissues. Colocalization analyses of AEC QTLs with asthma GWAS variants revealed potential molecular mechanisms of asthma, including QTLs at the TSLP locus that were common to both the RV and vehicle treatments and to both childhood onset and adult onset asthma, as well as QTLs at the 17q12-21 asthma locus that were specific to RV exposure and childhood onset asthma, consistent with clinical and epidemiological studies of these loci. CONCLUSIONS: This study provides evidence of functional effects for asthma risk variants in AECs and insight into RV-mediated transcriptional and epigenetic response mechanisms that modulate genetic effects in the airway and risk for asthma.

The development of tumour vascular networks.

The growth of solid tumours relies on an ever-increasing supply of oxygen and nutrients that are delivered via vascular networks. Tumour vasculature includes endothelial cell lined angiogenesis and the less common cancer cell lined vasculogenic mimicry (VM). To study and compare the development of vascular networks formed during angiogenesis and VM (represented here by breast cancer and pancreatic cancer cell lines) a number of in vitro assays were utilised. From live cell imaging, we performed a large-scale automated extraction of network parameters and identified properties not previously reported. We show that for both angiogenesis and VM, the characteristic network path length reduces over time; however, only endothelial cells increase network clustering coefficients thus maintaining small-world network properties as they develop. When compared to angiogenesis, the VM network efficiency is improved by decreasing the number of edges and vertices, and also by increasing edge length. Furthermore, our results demonstrate that angiogenic and VM networks appear to display similar properties to road traffic networks and are also subject to the well-known Braess paradox. This quantitative measurement framework opens up new avenues to potentially evaluate the impact of anti-cancer drugs and anti-vascular therapies.

Lifestyle Interventions in the Treatment of Obsessive-Compulsive and Related Disorders: A Systematic Review.

OBJECTIVE: Lifestyle medicine is increasingly important in psychiatry for its efficacy as a transdiagnostic treatment, its preventative potential, and its increased tolerability compared with first-line strategies. Although the impact of lifestyle medicine is strong across many psychiatric illnesses, our understanding of the effectiveness of lifestyle interventions in treating obsessive-compulsive and related disorders (OCRDs) is minimal. We aimed to conduct a systematic review examining the effect of lifestyle interventions (targeting diet, exercise, sleep, stress management, and tobacco/alcohol use) on OCRD symptoms. METHODS: We systematically searched four electronic databases for published randomized controlled trials reporting on lifestyle interventions for OCRDs. We qualitatively synthesized results of eligible studies and calculated mean changes in symptom severity from baseline to end point and standardized between-group effect sizes. RESULTS: We identified 33 eligible studies. Poor efficacy was noted across a number of rigorous dietary supplement interventions with some promising data in four (of six) studies regarding N-acetylcysteine for trichotillomania, skin picking, and obsessive-compulsive disorder. Stress management interventions, generally characterized by high risk of bias, reported mild effectiveness with greater effects noted for mind-body exercises (yoga) for obsessive-compulsive disorder. Greater improvements may be achieved when lifestyle intervention is adjunct to first-line treatments and delivered by facilitators. CONCLUSIONS: Diet (particularly N-acetylcysteine) and stress management interventions seem promising avenues for OCRDs treatment. We present an action plan to move the lifestyle interventions for OCRDs field forward. Further high-quality lifestyle interventions are required to improve the certainty of findings and to inform clinical treatment guidelines.Review Registration Number: CRD42020151407.

The YfkO Nitroreductase from Bacillus Licheniformis on Gold-Coated Superparamagnetic Nanoparticles: Towards a Novel Directed Enzyme Prodrug Therapy Approach.

The bacterial nitroreductase NfnB has been the focus of a great deal of research for its use in directed enzyme prodrug therapy in combination with the nitroreductase prodrug CB1954 with this combination of enzyme and prodrug even entering clinical trials. Despite some promising results, there are major limitations to this research, such as the fact that the lowest reported Km for this enzyme far exceeds the maximum dosage of CB1954. Due to these limitations, new enzymes are now being investigated for their potential use in directed enzyme prodrug therapy. One such enzyme that has proved promising is the YfkO nitroreductase from Bacillus Licheniformis. Upon investigation, the YfkO nitroreductase was shown to have a much lower Km (below the maximum dosage) than that of NfnB as well as the fact that when reacting with the prodrug it produces a much more favourable ratio of enzymatic products than NfnB, forming more of the desired 4-hydroxylamine derivative of CB1954.

Platelets disrupt vasculogenic mimicry by cancer cells.

Tumour vasculature supports the growth and progression of solid cancers with both angiogenesis (endothelial cell proliferation) and vasculogenic mimicry (VM, the formation of vascular structures by cancer cells themselves) predictors of poor patient outcomes. Increased circulating platelet counts also predict poor outcome for cancer patients but the influence of platelets on tumour vasculature is incompletely understood. Herein, we show with in vitro assays that platelets did not influence angiogenesis but did actively inhibit VM formation by cancer cell lines. Both platelet sized beads and the releasates from platelets were partially effective at inhibiting VM formation suggesting that direct contact maximises the effect. Platelets also promoted cancer cell invasion in vitro. B16F10 melanomas in Bcl-xPlt20/Plt20 thrombocytopenic mice showed a higher content of VM than their wildtype counterparts while angiogenesis did not differ. In a xenograft mouse model of breast cancer with low-dose aspirin to inactivate the platelets, the burden of MDA-MB-231-LM2 breast cancer cells was reduced and the gene expression profile of the cancer cells was altered; but no effect on tumour vasculature was observed. Taken together, this study provides new insights into the action of platelets on VM formation and their involvement in cancer progression.

Time dependent HPLC analysis of the product ratio of enzymatically reduced prodrug CB1954 by a modified and immobilised nitroreductase.

Directed enzyme prodrug therapy is a chemotherapy strategy that utilises prodrug-activating enzymes to activate prodrugs at the tumour location, thus reducing off-target effects. The most commonly investigated enzyme for use with the CB1954 prodrug is the NfnB nitroreductase from E. coli. Literature states that CB1954 is reduced by NfnB at the 2- or 4-position at a 1:1 ratio; deviation from this ratio has been observed in the literature, but not further investigated. The kinetic parameters for the genetically-modified enzymes; NfnB-his, NfnB-cys and AuNP-NfnB-cys were assessed and HPLC analysis was used to determine the hydroxylamine product ratios formed when reacted with CB1954. Time-dependent HPLC studies were carried out to assess how this ratio changes over time. It was shown that the hydroxylamine ratio formed by the reduction of CB1954 by a nitroreductase changes over time and that this change in ratio relates directly to the kinetics of the reaction. Thus, the hydroxylamine ratio measured using HPLC at a given time point was not a true indication of the preference of the nitroreductase enzymes during catalysis. These results question how nitroreductases are evaluated in terms of the hydroxylamine ratio and it is suspected that this phenomenon may also apply to other enzyme/prodrug combinations.

Global DNA methylation changes spanning puberty are near predicted estrogen-responsive genes and enriched for genes involved in endocrine and immune processes.

Background: The changes that occur during puberty have been implicated in susceptibility to a wide range of diseases later in life, many of which are characterized by sex-specific differences in prevalence. Both genetic and environmental factors have been associated with the onset or delay of puberty, and recent evidence has suggested a role for epigenetic changes in the initiation of puberty as well. Objective: To identify global DNA methylation changes that arise across the window of puberty in girls and boys. Methods: Genome-wide DNA methylation levels were measured using the Infinium 450K array. We focused our studies on peripheral blood mononuclear cells (PBMCs) from 30 girls and 25 boys pre- and post-puberty (8 and 14 years, respectively), in whom puberty status was confirmed by Tanner staging. Results: Our study revealed 347 differentially methylated probes (DMPs) in females and 50 DMPs in males between the ages of 8 and 14 years (FDR 5%). The female DMPs were in or near 312 unique genes, which were over-represented for having high affinity estrogen response elements (permutation P < 2.0 × 10-6), suggesting that some of the effects of estrogen signaling in puberty are modified through epigenetic mechanisms. Ingenuity Pathway Analysis (IPA) of the 312 genes near female puberty DMPs revealed significant networks enriched for immune and inflammatory responses as well as reproductive hormone signaling. Finally, analysis of gene expression in the female PBMCs collected at 14 years revealed modules of correlated transcripts that were enriched for immune and reproductive system functions, and include genes that are responsive to estrogen and androgen receptor signaling. The male DMPs were in or near 48 unique genes, which were enriched for adrenaline and noradrenaline biosynthesis (Enrichr P = 0.021), with no significant networks identified. Additionally, no modules were identified using post-puberty gene expression levels in males. Conclusion: Epigenetic changes spanning the window of puberty in females may be responsive to or modify hormonal changes that occur during this time and potentially contribute to sex-specific differences in immune-mediated and endocrine diseases later in life.

Role of the ß Common (ßc) Family of Cytokines in Health and Disease.

The ß common ([ßc]/CD131) family of cytokines comprises granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-3, and IL-5, all of which use ßc as their key signaling receptor subunit. This is a prototypic signaling subunit-sharing cytokine family that has unveiled many biological paradigms and structural principles applicable to the IL-2, IL-4, and IL-6 receptor families, all of which also share one or more signaling subunits. Originally identified for their functions in the hematopoietic system, the ßc cytokines are now known to be truly pleiotropic, impacting on multiple cell types, organs, and biological systems, and thereby controlling the balance between health and disease. This review will focus on the emerging biological roles for the ßc cytokines, our progress toward understanding the mechanisms of receptor assembly and signaling, and the application of this knowledge to develop exciting new therapeutic approaches against human disease.

From the Cover: Development and Application of a Dual Rat and Human AHR Activation Assay.

Significant prolonged aryl hydrocarbon receptor (AHR) activation, classically exhibited following exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin, can cause a variety of undesirable toxicological effects. Novel pharmaceutical chemistries also have the potential to cause activation of AHR and consequent toxicities in pre-clinical species and man. Previous methods either employed relatively expensive and low-throughput primary hepatocyte dosing with PCR endpoint, or low resolution overexpressing reporter gene assays. We have developed, validated and applied an in vitro microtitre plate imaging-based medium throughput screening assay for the assessment of endogenous species-specific AHR activation potential via detection of induction of the surrogate transcriptional target Cytochrome P450 CYP1A1. Routine testing of pharmaceutical drug development candidate chemistries using this assay can influence the chemical design process and highlight AHR liabilities. This assay should be introduced such that human AHR activation liability is flagged early for confirmatory testing.

Psychosocial, Demographic, and Illness-Related Factors Associated With Acute Traumatic Stress Responses in Parents of Children With a Serious Illness or Injury.

This study investigated factors associated with acute stress symptoms in parents of seriously ill children across a range of illnesses and treatment settings within a pediatric hospital setting. It was hypothesized that psychosocial variables would be more strongly associated with acute stress responses than demographic and child illness variables. Participants were 115 mothers and 56 fathers of children treated within the oncology, cardiology, and intensive care departments of a pediatric hospital. Acute stress, psychosocial, demographic, and medical data were collected within the first 4 weeks of the child's hospital admission. A robust hierarchical regression model revealed that psychosocial factors significantly explained 36.8% of the variance in parent acute stress responses (p < .001); demographic variables significantly added a further 4.5% (p = .022), but illness-related factors did not contribute to the model. Findings support the implementation of a general psychosocial screening approach for parents across the wider hospital system, and that psychosocial risk factors may be targeted in interventions across different illnesses and treatment settings to improve parent outcomes.

Fraction of exhaled nitric oxide values in childhood are associated with 17q11.2-q12 and 17q12-q21 variants.

BACKGROUND: The fraction of exhaled nitric oxide (Feno) value is a biomarker of eosinophilic airway inflammation and is associated with childhood asthma. Identification of common genetic variants associated with childhood Feno values might help to define biological mechanisms related to specific asthma phenotypes. OBJECTIVE: We sought to identify the genetic variants associated with childhood Feno values and their relation with asthma. METHODS: Feno values were measured in children age 5 to 15 years. In 14 genome-wide association studies (N = 8,858), we examined the associations of approximately 2.5 million single nucleotide polymorphisms (SNPs) with Feno values. Subsequently, we assessed whether significant SNPs were expression quantitative trait loci in genome-wide expression data sets of lymphoblastoid cell lines (n = 1,830) and were related to asthma in a previously published genome-wide association data set (cases, n = 10,365; control subjects: n = 16,110). RESULTS: We identified 3 SNPs associated with Feno values: rs3751972 in LYR motif containing 9 (LYRM9; P = 1.97 × 10(-10)) and rs944722 in inducible nitric oxide synthase 2 (NOS2; P = 1.28 × 10(-9)), both of which are located at 17q11.2-q12, and rs8069176 near gasdermin B (GSDMB; P = 1.88 × 10(-8)) at 17q12-q21. We found a cis expression quantitative trait locus for the transcript soluble galactoside-binding lectin 9 (LGALS9) that is in linkage disequilibrium with rs944722. rs8069176 was associated with GSDMB and ORM1-like 3 (ORMDL3) expression. rs8069176 at 17q12-q21, but not rs3751972 and rs944722 at 17q11.2-q12, were associated with physician-diagnosed asthma. CONCLUSION: This study identified 3 variants associated with Feno values, explaining 0.95% of the variance. Identification of functional SNPs and haplotypes in these regions might provide novel insight into the regulation of Feno values. This study highlights that both shared and distinct genetic factors affect Feno values and childhood asthma.

Genome-wide association study of lung function phenotypes in a founder population.

BACKGROUND: Lung function is a long-term predictor of mortality and morbidity. OBJECTIVE: We sought to identify single nucleotide polymorphisms (SNPs) associated with lung function. METHODS: We performed a genome-wide association study (GWAS) of FEV1, forced vital capacity (FVC), and FEV1/FVC in 1144 Hutterites aged 6 to 89 years, who are members of a founder population of European descent. We performed least absolute shrinkage and selection operation regression to select the minimum set of SNPs that best predict FEV1/FVC in the Hutterites and used the GRAIL algorithm to mine the Gene Ontology database for evidence of functional connections between genes near the predictive SNPs. RESULTS: Our GWAS identified significant associations between FEV1/FVC and SNPs at the THSD4-UACA-TLE3 locus on chromosome 15q23 (P = 5.7 × 10(-8) to 3.4 × 10(-9)). Nine SNPs at or near 4 additional loci had P < 10(-5) with FEV1/FVC. Only 2 SNPs were found with P < 10(-5) for FEV1 or FVC. We found nominal levels of significance with SNPs at 9 of the 27 previously reported loci associated with lung function measures. Among a predictive set of 80 SNPs, 6 loci were identified that had a significant degree of functional connectivity (GRAIL P < .05), including 3 clusters of ß-defensin genes, 2 chemokine genes (CCL18 and CXCL12), and TNFRSF13B. CONCLUSION: This study identifies genome-wide significant associations and replicates results of previous GWASs. Multimarker modeling implicated for the first time common variation in genes involved in antimicrobial immunity in airway mucosa that influences lung function.