ABSTRACT
PURPOSE OF REVIEW: This review evaluates the current literature on ileus, impaired gastrointestinal transit (IGT), and acute gastrointestinal injury (AGI) and its impact on multiple organ dysfunction syndrome. RECENT FINDINGS: Ileus is often under recognized in critically ill patients and is associated with significant morbidity and is potentially a marker of disease severity as seen in other organs like kidneys (ATN).
Subject(s)
Critical Illness , Ileus , Multiple Organ Failure , Humans , Multiple Organ Failure/etiology , Multiple Organ Failure/physiopathology , Multiple Organ Failure/diagnosis , Ileus/etiology , Ileus/physiopathology , Ileus/diagnosis , Gastrointestinal Transit/physiologyABSTRACT
PURPOSE: Antimicrobial stewardship programs (ASPs) have been a challenge in less resourceful health care settings. Medical smartphone applications (apps) can be accessible tools to support ASPs under such circumstances. A hospital-specific ASP app was prepared and the acceptance and usability of the study ASP app were evaluated by physicians and pharmacists in 2 community-based academic hospitals. METHODS: The exploratory survey was conducted 5 months following the implementation of the study ASP app. A questionnaire was developed, and the validity and reliability were analyzed using S-CVI/Ave (scale content validity index/Average) and Cronbach's alpha, respectively. The questionnaire consisted of demographics (3 items), acceptance (9 items), usability (10 items), and barriers (2 items). Descriptive analysis was conducted using a 5-point Likert scale, multiple selections, and free-text responses. RESULTS: Approximately 38.7% of 75 respondents (response rate, 23.5%) used the app. Most scored 4 or higher, indicating that the study ASP app was easy to install (89.7%), use (79.3%), and apply to clinical settings (69.0%). Frequently used contents were dosing (39.6%), the spectrum of activity (7.1%), and intravenous-to-oral conversion (7.1%). Barriers included limited time (38.2%) and insufficient content (20.6%). Users indicated that the study ASP app helped improve their knowledge on treatment guidelines (72.4%), antibiotic use (62.1%), and adverse reactions (69.0%). CONCLUSION: The study ASP app was well accepted by physicians and pharmacists and it can be useful to supplement ASPs activities in less resourceful hospitals with a large burden of patient care.
Subject(s)
Antimicrobial Stewardship , Mobile Applications , Physicians , Humans , Pharmacists , Smartphone , Reproducibility of Results , Anti-Bacterial Agents/therapeutic use , HospitalsABSTRACT
Research suggests that the information needs of patients diagnosed with head and neck cancer can be particularly complex, given the frequent need for multidisciplinary treatments and resulting potential for profound functional impairments. This study was designed to identify head and neck cancer patients' reported informational needs and to evaluate their satisfaction with the written information they received. The study was divided into 2 phases: phase 1, prior to development of a new educational pamphlet, and phase 2, after its implementation. A survey was designed to evaluate several measures including content, amount, understanding, and timing of information delivery. It was distributed at two points during patients' treatment pathway for each phase: at their last radiation appointment and at their posttreatment follow-up appointment. Participant responses after the revised pamphlet indicated greater preparedness before their first treatment, as well as increased satisfaction with treatment option information. Most were satisfied with information timing, but about a third did indicate that additional information would have been helpful at variable time points. Open-ended responses demonstrated that overall, patients do still desire more information, particularly on side effect and self-care management information. While patients with head and neck cancer appear to be generally satisfied with the written information received, our findings suggest that there is still considerable variability in how the information is understood, when it should be delivered, and in which areas more would have been beneficial. These findings underscore the need to consider how best to balance available resources in order to provide more tailored yet comprehensive education for this group of patients.
Subject(s)
Head and Neck Neoplasms , Patient Satisfaction , Head and Neck Neoplasms/radiotherapy , Humans , Surveys and QuestionnairesABSTRACT
Autozygosity mapping (AM) is a technique utilised for mapping homozygous autosomal recessive (AR) traits and facilitation of genetic diagnosis. We investigated the utility of AM for the molecular diagnosis of heterogeneous AR disorders, using epidermolysis bullosa (EB) as a paradigm. We applied this technique to a cohort of 46 distinct EB families using both short tandem repeat (STR) and genome-wide single nucleotide polymorphism (SNP) array-based AM to guide targeted Sanger sequencing of EB candidate genes. Initially, 39 of the 46 cases were diagnosed with homozygous mutations using this method. Independently, 26 cases, including the seven initially unresolved cases, were analysed with an EB-targeted next-generation sequencing (NGS) panel. NGS identified mutations in five additional cases, initially undiagnosed due to the presence of compound heterozygosity, deep intronic mutations or runs of homozygosity below the set threshold of 2 Mb, for a total yield of 44 of 46 cases (95.7%) diagnosed genetically.
Subject(s)
Consanguinity , Epidermolysis Bullosa/genetics , Genome-Wide Association Study , Microsatellite Repeats , Polymorphism, Single Nucleotide , Chromosome Mapping , Epidermolysis Bullosa/diagnosis , Female , Genes, Recessive , High-Throughput Nucleotide Sequencing , Homozygote , Humans , Male , Sequence Analysis, DNAABSTRACT
Congenital left-sided lesions (LSLs) are serious, heritable malformations of the heart. However, little is known about the genetic causes of LSLs. This study was undertaken to identify common variants acting through the genotype of the affected individual (i.e. case) or the mother (e.g. via an in utero effect) that influence the risk of LSLs. A genome-wide association study (GWAS) was performed using data from 377 LSL case-parent triads, with follow-up studies in an independent sample of 224 triads and analysis of the combined data. Associations with both the case and maternal genotypes were assessed using log-linear analyses under an additive model. An association between LSLs and the case genotype for one intergenic SNP on chromosome 16 achieved genome-wide significance in the combined data (rs8061121, combined P = 4.0 × 10(-9); relative risk to heterozygote: 2.6, 95% CI: 1.9-3.7). In the combined data, there was also suggestive evidence of association between LSLs and the case genotype for a variant in the synaptoporin gene (rs1975649, combined P = 3.4 × 10(-7); relative risk to heterozygote: 1.6, 95% CI: 1.4-2.0) and between LSLs and the maternal genotype for an intergenic SNP on chromosome 10 (rs11008222, combined P = 6.3 × 10(-7); relative risk to heterozygote: 1.6, 95% CI: 1.4-2.0). This is the first GWAS of LSLs to evaluate associations with both the case and maternal genotypes. The results of this study identify three candidate LSL susceptibility loci, including one that appears to be associated with the risk of LSLs via the maternal genotype.
Subject(s)
Chromosomes, Human, Pair 10/genetics , Chromosomes, Human, Pair 16/genetics , Genome-Wide Association Study/methods , Heart Defects, Congenital/genetics , Synaptophysin/genetics , Female , Genetic Predisposition to Disease , Genotype , Heart Defects, Congenital/pathology , Humans , Male , Maternal-Fetal Exchange , Polymorphism, Single Nucleotide , PregnancyABSTRACT
Food allergy is a significant public health concern, especially among children. Previous candidate gene studies suggested a few susceptibility loci for food allergy, but no study investigated the contribution of copy number variations (CNVs) to food allergy on a genome-wide scale. To investigate the genetics of food allergy, we performed CNV assessment using high-resolution genome-wide single nucleotide polymorphism arrays. CNV calls from a total of 357 cases with confirmed food allergy and 3980 controls were analyzed within a discovery cohort, followed by a replication analysis composed of 167 cases and 1573 controls. We identified that CNVs in CTNNA3 were significantly associated with food allergy in both the discovery cohort and the replication cohort. Of particular interest, CTNNA3 CNVs hit exons or intron regions rich in histone marker H3K4Me1. CNVs in a second gene (RBFOX1) showed a significant association (p = 7.35 × 10(-5)) with food allergy at the genome-wide level in our meta-analysis of the European ancestry cohorts. The presence of these CNVs was confirmed by quantitative PCR. Furthermore, knockdown of CTNNA3 resulted in upregulation of CD63 and CD203c in mononuclear cells upon PMA stimulation, suggesting a role in sensitization to allergen. We uncovered at least two plausible genes harboring CNV loci that are enriched in pediatric patients with food allergies. The novel gene candidates discovered in this study by genome-wide CNV analysis are compelling drug and diagnostic targets for food allergy.
Subject(s)
DNA Copy Number Variations , Food Hypersensitivity/genetics , Food Hypersensitivity/immunology , Genetic Predisposition to Disease , RNA-Binding Proteins/genetics , alpha Catenin/genetics , Adolescent , Age Factors , Case-Control Studies , Child , Child, Preschool , Female , Gene Deletion , Genetic Association Studies , Humans , Male , Meta-Analysis as Topic , Middle Aged , Polymorphism, Single Nucleotide , RNA Splicing Factors , RNA, Small Interfering , Reproducibility of ResultsABSTRACT
Neuroblastoma is a childhood cancer of the sympathetic nervous system that accounts for approximately 10% of all paediatric oncology deaths. To identify genetic risk factors for neuroblastoma, we performed a genome-wide association study (GWAS) on 2,251 patients and 6,097 control subjects of European ancestry from four case series. Here we report a significant association within LIM domain only 1 (LMO1) at 11p15.4 (rs110419, combined P = 5.2 × 10(-16), odds ratio of risk allele = 1.34 (95% confidence interval 1.25-1.44)). The signal was enriched in the subset of patients with the most aggressive form of the disease. LMO1 encodes a cysteine-rich transcriptional regulator, and its paralogues (LMO2, LMO3 and LMO4) have each been previously implicated in cancer. In parallel, we analysed genome-wide DNA copy number alterations in 701 primary tumours. We found that the LMO1 locus was aberrant in 12.4% through a duplication event, and that this event was associated with more advanced disease (P < 0.0001) and survival (P = 0.041). The germline single nucleotide polymorphism (SNP) risk alleles and somatic copy number gains were associated with increased LMO1 expression in neuroblastoma cell lines and primary tumours, consistent with a gain-of-function role in tumorigenesis. Short hairpin RNA (shRNA)-mediated depletion of LMO1 inhibited growth of neuroblastoma cells with high LMO1 expression, whereas forced expression of LMO1 in neuroblastoma cells with low LMO1 expression enhanced proliferation. These data show that common polymorphisms at the LMO1 locus are strongly associated with susceptibility to developing neuroblastoma, but also may influence the likelihood of further somatic alterations at this locus, leading to malignant progression.
Subject(s)
DNA-Binding Proteins/genetics , Genetic Predisposition to Disease/genetics , Genome-Wide Association Study , Neuroblastoma/genetics , Oncogenes/genetics , Transcription Factors/genetics , Alleles , Cell Line, Tumor , Cell Proliferation , Chromosomes, Human, Pair 11/genetics , DNA Copy Number Variations/genetics , Disease Progression , Europe/ethnology , Gene Duplication/genetics , Gene Expression Regulation, Neoplastic/genetics , Genome, Human/genetics , Genomics , Genotype , Humans , LIM Domain Proteins , Neuroblastoma/pathology , Odds Ratio , Phenotype , Polymorphism, Single Nucleotide/genetics , Survival RateABSTRACT
We performed risk assessment for Crohn's disease (CD) and ulcerative colitis (UC), the two common forms of inflammatory bowel disease (IBD), by using data from the International IBD Genetics Consortium's Immunochip project. This data set contains ~17,000 CD cases, ~13,000 UC cases, and ~22,000 controls from 15 European countries typed on the Immunochip. This custom chip provides a more comprehensive catalog of the most promising candidate variants by picking up the remaining common variants and certain rare variants that were missed in the first generation of GWAS. Given this unprecedented large sample size and wide variant spectrum, we employed the most recent machine-learning techniques to build optimal predictive models. Our final predictive models achieved areas under the curve (AUCs) of 0.86 and 0.83 for CD and UC, respectively, in an independent evaluation. To our knowledge, this is the best prediction performance ever reported for CD and UC to date.
Subject(s)
Colitis, Ulcerative/genetics , Crohn Disease/genetics , Models, Genetic , Area Under Curve , Case-Control Studies , Genetic Association Studies , Genetic Predisposition to Disease , Humans , Linkage Disequilibrium , Logistic Models , Polymorphism, Single Nucleotide , Risk Assessment/methods , Risk Factors , Sample Size , Support Vector MachineABSTRACT
Infantile myofibromatosis (IM) is a disorder of mesenchymal proliferation characterized by the development of nonmetastasizing tumors in the skin, muscle, bone, and viscera. Occurrence within families across multiple generations is suggestive of an autosomal-dominant (AD) inheritance pattern, but autosomal-recessive (AR) modes of inheritance have also been proposed. We performed whole-exome sequencing (WES) in members of nine unrelated families clinically diagnosed with AD IM to identify the genetic origin of the disorder. In eight of the families, we identified one of two disease-causing mutations, c.1978C>A (p.Pro660Thr) and c.1681C>T (p.Arg561Cys), in PDGFRB. Intriguingly, one family did not have either of these PDGFRB mutations but all affected individuals had a c.4556T>C (p.Leu1519Pro) mutation in NOTCH3. Our studies suggest that mutations in PDGFRB are a cause of IM and highlight NOTCH3 as a candidate gene. Further studies of the crosstalk between PDGFRB and NOTCH pathways may offer new opportunities to identify mutations in other genes that result in IM and is a necessary first step toward understanding the mechanisms of both tumor growth and regression and its targeted treatment.
Subject(s)
Genes, Dominant , Mutation, Missense , Myofibromatosis/congenital , Receptor, Platelet-Derived Growth Factor beta/genetics , Amino Acid Sequence , Base Sequence , Female , Genetic Association Studies , Humans , Male , Myofibromatosis/genetics , Pedigree , Receptor, Notch3 , Receptors, Notch/genetics , Sequence Analysis, DNAABSTRACT
BACKGROUND: Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease among children, the etiology of which involves a strong genetic component, but much of the underlying genetic determinants still remain unknown. Our aim was to identify novel genetic variants that predispose to JIA. METHODS: We performed a genome-wide association study (GWAS) and replication in a total of 1166 JIA cases and 9500 unrelated controls of European ancestry. Correlation of SNP genotype and gene expression was investigated. Then we conducted targeted resequencing of a candidate locus, among a subset of 480 cases and 480 controls. SUM test was performed to evaluate the association of the identified rare functional variants. RESULTS: The CXCR4 locus on 2q22.1 was found to be significantly associated with JIA, peaking at SNP rs953387. However, this result is subjected to subpopulation stratification within the subjects of European ancestry. After adjusting for principal components, nominal significant association remained (p < 10(-4)). Because of its interesting known function in immune regulation, we carried out further analyses to assess its relationship with JIA. Expression of CXCR4 was correlated with CXCR4 rs953387 genotypes in lymphoblastoid cell lines (p = 0.014) and T-cells (p = 0.0054). In addition, rare non-synonymous and stop-gain sequence variants in CXCR4, putatively damaging for CXCR4 function, were significantly enriched in JIA cases (p = 0.015). CONCLUSION: Our results suggest the association of CXCR4 variants with JIA, implicating that this gene may be involved in the pathogenesis of autoimmune disease. However, because this locus is subjected to population stratification within the subjects of European ancestry, additional replication is still necessary for this locus to be considered a true risk locus for JIA. This cell-surface chemokine receptor has already been targeted in other diseases and may serve as a tractable therapeutic target for a specific subset of pediatric arthritis patients with additional replication and functional validation of the locus.
Subject(s)
Arthritis, Juvenile/genetics , Genetic Predisposition to Disease , Receptors, CXCR4/genetics , Adolescent , Amino Acid Sequence , Case-Control Studies , Child , Child, Preschool , Female , Genetic Loci , Genome-Wide Association Study , Genotyping Techniques , Humans , Male , Molecular Sequence Data , Polymorphism, Single Nucleotide , Principal Component Analysis , Sequence Analysis, DNA , White People/geneticsABSTRACT
BACKGROUND: Copy number variation (CNV) is a potential contributing factor to many genetic diseases. Here we investigated the potential association of CNV with nonsyndromic cryptorchidism, the most common male congenital genitourinary defect, in a Caucasian population. METHODS: Genome wide genotyping were performed in 559 cases and 1772 controls (Group 1) using Illumina HumanHap550 v1, HumanHap550 v3 or Human610-Quad platforms and in 353 cases and 1149 controls (Group 2) using the Illumina Human OmniExpress 12v1 or Human OmniExpress 12v1-1. Signal intensity data including log R ratio (LRR) and B allele frequency (BAF) for each single nucleotide polymorphism (SNP) were used for CNV detection using PennCNV software. After sample quality control, gene- and CNV-based association tests were performed using cleaned data from Group 1 (493 cases and 1586 controls) and Group 2 (307 cases and 1102 controls) using ParseCNV software. Meta-analysis was performed using gene-based test results as input to identify significant genes, and CNVs in or around significant genes were identified in CNV-based association test results. Called CNVs passing quality control and signal intensity visualization examination were considered for validation using TaqMan CNV assays and QuantStudio® 3D Digital PCR System. RESULTS: The meta-analysis identified 373 genome wide significant (p < 5X10-4) genes/loci including 49 genes/loci with deletions and 324 with duplications. Among them, 17 genes with deletion and 1 gene with duplication were identified in CNV-based association results in both Group 1 and Group 2. Only 2 genes (NUCB2 and UPF2) containing deletions passed CNV quality control in both groups and signal intensity visualization examination, but laboratory validation failed to verify these deletions. CONCLUSIONS: Our data do not support that structural variation is a major cause of nonsyndromic cryptorchidism.
Subject(s)
Cryptorchidism/genetics , DNA Copy Number Variations , White People/genetics , Genome-Wide Association Study , Humans , Male , SoftwareABSTRACT
BACKGROUND: Ehlers Danlos Syndrome is a rare form of inherited connective tissue disorder, which primarily affects skin, joints, muscle, and blood cells. The current study aimed at finding the mutation that causing EDS type VII C also known as "Dermatosparaxis" in this family. METHODS: Through systematic data querying of the electronic medical records (EMRs) of over 80,000 individuals, we recently identified an EDS family that indicate an autosomal dominant inheritance. The family was consented for genomic analysis of their de-identified data. After a negative screen for known mutations, we performed whole genome sequencing on the male proband, his affected father, and unaffected mother. We filtered the list of non-synonymous variants that are common between the affected individuals. RESULTS: The analysis of non-synonymous variants lead to identifying a novel mutation in the ADAMTSL2 (p. Gly421Ser) gene in the affected individuals. Sanger sequencing confirmed the mutation. CONCLUSION: Our work is significant not only because it sheds new light on the pathophysiology of EDS for the affected family and the field at large, but also because it demonstrates the utility of unbiased large-scale clinical recruitment in deciphering the genetic etiology of rare mendelian diseases. With unbiased large-scale clinical recruitment we strive to sequence as many rare mendelian diseases as possible, and this work in EDS serves as a successful proof of concept to that effect.
Subject(s)
ADAM Proteins/genetics , Data Mining/methods , Databases, Genetic , Ehlers-Danlos Syndrome/genetics , Genetic Variation/genetics , ADAMTS Proteins , Child , Ehlers-Danlos Syndrome/diagnosis , Female , Humans , Male , PedigreeABSTRACT
BACKGROUND: Systemic sclerosis (SSc) is a rheumatologic disease with a multifactorial etiology. Genome-wide association studies imply a polygenic, complex mode of inheritance with contributions from variation at the human leukocyte antigen locus and non-coding variation at a locus on chromosome 6p21, among other modestly impactful loci. Here we describe an 8-year-old female proband presenting with diffuse cutaneous SSc/scleroderma and a family history of SSc in a grandfather and maternal aunt. METHODS: We employed whole exome sequencing (WES) of three members of this family. We examined rare missense, nonsense, splice-altering, and coding indels matching an autosomal dominant inheritance model. We selected one missense variant for Sanger sequencing confirmation based on its predicted impact on gene function and location in a known SSc genetic locus. RESULTS: Bioinformatic analysis found eight candidate variants meeting our criteria. We identified a very rare missense variant in the regulatory NODP domain of NOTCH4 located at the 6p21 locus, c.4245G > A:p.Met1415Ile, segregating with the phenotype. This allele has a frequency of 1.83 × 10-5 by the data of the Exome Aggregation Consortium. CONCLUSION: This family suggests a novel mechanism of SSc pathogenesis in which a rare and penetrant coding variation can substantially elevate disease risk in contrast to the more modest non-coding variation typically found at this locus. These results suggest that modulation of the NOTCH4 gene might be responsible for the association signal at chromosome 6p21 in SSc.
Subject(s)
Exome/genetics , Genes, Dominant/genetics , Mutation, Missense , Receptor, Notch4/genetics , Scleroderma, Systemic/genetics , Alleles , Child , Chromosomes, Human, Pair 6/genetics , Computational Biology , Female , Genetic Predisposition to Disease , Grandparents , Heterozygote , Humans , Male , Pedigree , Penetrance , Protein Domains/genetics , Sequence Analysis, DNAABSTRACT
BACKGROUND: Common variable immunodeficiency (CVID) is characterized clinically by inadequate quantity and quality of serum immunoglobulins with increased susceptibility to infections, resulting in significant morbidity and mortality. Only a few genes have been uncovered, and the genetic background of CVID remains elusive to date for the majority of patients. OBJECTIVE: We sought to seek novel associations of genes and genetic variants with CVID. METHODS: We performed association analyses in a discovery cohort of 164 patients with CVID and 19,542 healthy control subjects genotyped on the Immuno BeadChip from Illumina platform; replication of findings was examined in an independent cohort of 135 patients with CVID and 2,066 healthy control subjects, followed by meta-analysis. RESULTS: We identified 11 single nucleotide polymorphisms (SNPs) at the 16p11.2 locus associated with CVID at a genome-wide significant level in the discovery cohort. The most significant SNP, rs929867 (P = 6.21 × 10(-9)), is in the gene fused-in-sarcoma (FUS), with 4 other SNPs mapping to integrin CD11b (ITGAM). Results were confirmed in our replication cohort. Conditional association analysis suggests a single association signal at the 16p11.2 locus. A strong trend of association was also seen for 38 SNPs (P < 5 × 10(-5)) in the MHC region, supporting that this is a genuine CVID locus. Interestingly, we found that 80% of patients with the rare ITGAM variants have reduced switched memory B-cell counts. CONCLUSION: We report a novel association of CVID with rare variants at the FUS/ITGAM (CD11b) locus on 16p11.2. The association signal is enriched for promoter/enhancer markers in the ITGAM gene. ITGAM encodes the integrin CD11b, a part of complement receptor 3, a novel candidate gene implicated here for the first time in the pathogenesis of CVID.
Subject(s)
CD11b Antigen/genetics , Chromosomes, Human, Pair 16 , Common Variable Immunodeficiency/genetics , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , RNA-Binding Protein FUS/genetics , Adult , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , B-Lymphocytes/pathology , CD11b Antigen/immunology , Case-Control Studies , Child, Preschool , Cohort Studies , Common Variable Immunodeficiency/diagnosis , Common Variable Immunodeficiency/immunology , Common Variable Immunodeficiency/pathology , Enhancer Elements, Genetic , Female , Genetic Loci , Humans , Immunologic Memory , Linkage Disequilibrium , Male , Promoter Regions, Genetic , RNA-Binding Protein FUS/immunologyABSTRACT
Hematological traits are important clinical indicators, the genetic determinants of which have not been fully investigated. Common measures of hematological traits include red blood cell (RBC) count, hemoglobin concentration (HGB), hematocrit (HCT), mean corpuscular hemoglobin (MCH), MCH concentration (MCHC), mean corpuscular volume (MCV), platelet count (PLT) and white blood cell (WBC) count. We carried out a genome-wide association study of the eight common hematological traits among 7943 African-American children and 6234 Caucasian children. In African Americans, we report five novel associations of HBE1 variants with HCT and MCHC, the alpha-globin gene cluster variants with RBC and MCHC, and a variant at the ARHGEF3 locus with PLT, as well as replication of four previously reported loci at genome-wide significance. In Caucasians, we report a novel association of variants at the COPZ1 locus with PLT as well as replication of four previously reported loci at genome-wide significance. Extended analysis of an association observed between MCH and the alpha-globin gene cluster variants demonstrated independent effects and epistatic interaction at the locus, impacting the risk of iron deficiency anemia in African Americans with specific genotype states. In summary, we extend the understanding of genetic variants underlying hematological traits based on analyses in African-American children.
Subject(s)
Anemia, Iron-Deficiency/genetics , Black or African American/genetics , Epistasis, Genetic , Genome-Wide Association Study , White People/genetics , Anemia, Iron-Deficiency/blood , Anemia, Iron-Deficiency/ethnology , Erythrocyte Indices , Erythrocytes/metabolism , Genetic Loci , Genetic Predisposition to Disease , Genotype , Guanine Nucleotide Exchange Factors/genetics , Humans , Polymorphism, Single Nucleotide , Rho Guanine Nucleotide Exchange Factors , alpha-Globins/geneticsABSTRACT
To identify genetic factors contributing to type 2 diabetes (T2D), we performed large-scale meta-analyses by using a custom â¼50,000 SNP genotyping array (the ITMAT-Broad-CARe array) with â¼2000 candidate genes in 39 multiethnic population-based studies, case-control studies, and clinical trials totaling 17,418 cases and 70,298 controls. First, meta-analysis of 25 studies comprising 14,073 cases and 57,489 controls of European descent confirmed eight established T2D loci at genome-wide significance. In silico follow-up analysis of putative association signals found in independent genome-wide association studies (including 8,130 cases and 38,987 controls) performed by the DIAGRAM consortium identified a T2D locus at genome-wide significance (GATAD2A/CILP2/PBX4; p = 5.7 × 10(-9)) and two loci exceeding study-wide significance (SREBF1, and TH/INS; p < 2.4 × 10(-6)). Second, meta-analyses of 1,986 cases and 7,695 controls from eight African-American studies identified study-wide-significant (p = 2.4 × 10(-7)) variants in HMGA2 and replicated variants in TCF7L2 (p = 5.1 × 10(-15)). Third, conditional analysis revealed multiple known and novel independent signals within five T2D-associated genes in samples of European ancestry and within HMGA2 in African-American samples. Fourth, a multiethnic meta-analysis of all 39 studies identified T2D-associated variants in BCL2 (p = 2.1 × 10(-8)). Finally, a composite genetic score of SNPs from new and established T2D signals was significantly associated with increased risk of diabetes in African-American, Hispanic, and Asian populations. In summary, large-scale meta-analysis involving a dense gene-centric approach has uncovered additional loci and variants that contribute to T2D risk and suggests substantial overlap of T2D association signals across multiple ethnic groups.
Subject(s)
Diabetes Mellitus, Type 2/genetics , Genetic Loci , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Diabetes Mellitus, Type 2/ethnology , Ethnicity , Female , Follow-Up Studies , Genetic Predisposition to Disease , Genome-Wide Association Study/methods , Genotype , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide , Young AdultABSTRACT
PURPOSE: Based on a genome-wide association study of testicular dysgenesis syndrome showing a possible association with TGFBR3, we analyzed data from a larger, phenotypically restricted cryptorchidism population for potential replication of this signal. MATERIALS AND METHODS: We excluded samples based on strict quality control criteria, leaving 844 cases and 2,718 controls of European ancestry that were analyzed in 2 separate groups based on genotyping platform (ie Illumina® HumanHap550, version 1 or 3, or Human610-Quad, version 1 BeadChip in group 1 and Human OmniExpress 12, version 1 BeadChip platform in group 2). Analyses included genotype imputation at the TGFBR3 locus, association analysis of imputed data with correction for population substructure, subsequent meta-analysis of data for groups 1 and 2, and selective genotyping of independent cases (330) and controls (324) for replication. We also measured Tgfbr3 mRNA levels and performed TGFBR3/betaglycan immunostaining in rat fetal gubernaculum. RESULTS: We identified suggestive (p ≤ 1× 10(-4)) association of markers in/near TGFBR3, including rs9661103 (OR 1.40; 95% CI 1.20, 1.64; p = 2.71 × 10(-5)) and rs10782968 (OR 1.58; 95% CI 1.26, 1.98; p = 9.36 × 10(-5)) in groups 1 and 2, respectively. In subgroup analyses we observed strongest association of rs17576372 (OR 1.42; 95% CI 1.24, 1.60; p = 1.67 × 10(-4)) with proximal and rs11165059 (OR 1.32; 95% CI 1.15, 1.38; p = 9.42 × 10(-4)) with distal testis position, signals in strong linkage disequilibrium with rs9661103 and rs10782968, respectively. Association of the prior genome-wide association study signal (rs12082710) was marginal (OR 1.13; 95% CI 0.99, 1.28; p = 0.09 for group 1), and we were unable to replicate signals in our independent cohort. Tgfbr3/betaglycan was differentially expressed in wild-type and cryptorchid rat fetal gubernaculum. CONCLUSIONS: These data suggest complex or phenotype specific association of cryptorchidism with TGFBR3 and the gubernaculum as a potential target of TGFß signaling.
Subject(s)
Cryptorchidism/genetics , Proteoglycans/genetics , Receptors, Transforming Growth Factor beta/genetics , Child , Child, Preschool , Humans , Infant , Male , PhenotypeABSTRACT
STUDY QUESTION: What are the genetic loci that increase susceptibility to nonsyndromic cryptorchidism, or undescended testis? SUMMARY ANSWER: A genome-wide association study (GWAS) suggests that susceptibility to cryptorchidism is heterogeneous, with a subset of suggestive signals linked to cytoskeleton-dependent functions and syndromic forms of the disease. WHAT IS KNOWN ALREADY: Population studies suggest moderate genetic risk of cryptorchidism and possible maternal and environmental contributions to risk. Previous candidate gene analyses have failed to identify a major associated locus, although variants in insulin-like 3 (INSL3), relaxin/insulin-like family peptide receptor 2 (RXFP2) and other hormonal pathway genes may increase risk in a small percentage of patients. STUDY DESIGN, SIZE, DURATION: This is a case-control GWAS of 844 boys with nonsyndromic cryptorchidism and 2718 control subjects without syndromes or genital anomalies, all of European ancestry. PARTICIPANTS/MATERIALS, SETTING, METHODS: All boys with cryptorchidism were diagnosed and treated by a pediatric specialist. In the discovery phase, DNA was extracted from tissue or blood samples and genotyping performed using the Illumina HumanHap550 and Human610-Quad (Group 1) or OmniExpress (Group 2) platform. We imputed genotypes genome-wide, and combined single marker association results in meta-analyses for all cases and for secondary subphenotype analyses based on testis position, laterality and age, and defined genome-wide significance as P = 7 × 10(-9) to correct for multiple testing. Selected markers were genotyped in an independent replication group of European cases (n = 298) and controls (n = 324). We used several bioinformatics tools to analyze top (P < 10(-5)) and suggestive (P < 10(-3)) signals for significant enrichment of signaling pathways, cellular functions and custom gene lists after multiple testing correction. MAIN RESULTS AND THE ROLE OF CHANCE: In the full analysis, we identified 20 top loci, none reaching genome-wide significance, but one passing this threshold in a subphenotype analysis of proximal testis position (rs55867206, near SH3PXD2B, odds ratio = 2.2 (95% confidence interval 1.7, 2.9), P = 2 × 10(-9)). An additional 127 top loci emerged in at least one secondary analysis, particularly of more severe phenotypes. Cytoskeleton-dependent molecular and cellular functions were prevalent in pathway analysis of suggestive signals, and may implicate loci encoding cytoskeletal proteins that participate in androgen receptor signaling. Genes linked to human syndromic cryptorchidism, including hypogonadotropic hypogonadism, and to hormone-responsive and/or differentially expressed genes in normal and cryptorchid rat gubernaculum, were also significantly overrepresented. No tested marker showed significant replication in an independent population. The results suggest heterogeneous, multilocus and potentially multifactorial susceptibility to nonsyndromic cryptorchidism. LIMITATIONS, REASONS FOR CAUTION: The present study failed to identify genome-wide significant markers associated with cryptorchidism that could be replicated in an independent population, so further studies are required to define true positive signals among suggestive loci. WIDER IMPLICATIONS OF THE FINDINGS: As the only GWAS to date of nonsyndromic cryptorchidism, these data will provide a basis for future efforts to understand genetic susceptibility to this common reproductive anomaly and the potential for additive risk from environmental exposures. STUDY FUNDING/COMPETING INTERESTS: This work was supported by R01HD060769 (the Eunice Kennedy Shriver National Institute for Child Health and Human Development (NICHD)), P20RR20173 (the National Center for Research Resources (NCRR), currently P20GM103464 from the National Institute of General Medical Sciences (NIGMS)), an Institute Development Fund to the Center for Applied Genomics at The Children's Hospital of Philadelphia, and Nemours Biomedical Research. The authors have no competing interests to declare.
Subject(s)
Cryptorchidism/diagnosis , Cytoskeleton/metabolism , Case-Control Studies , Child , Child, Preschool , Cryptorchidism/genetics , Genetic Markers , Genetic Predisposition to Disease , Genome-Wide Association Study , Genotype , Humans , Insulin/genetics , Male , Odds Ratio , Phenotype , Protein Structure, Tertiary , Proteins/genetics , Receptors, G-Protein-Coupled/genetics , Signal Transduction , Testis/pathologyABSTRACT
Teebi hypertelorism syndrome is a rare autosomal dominant disorder that has eluded a molecular etiology since first described in 1987. Here we report on two unrelated families with a Teebi hypertelorism-like syndrome and Teebi hypertelorism phenotype who have missense mutations in Sperm Antigen With Calponin Homology And Coiled-Coil Domains (SPECC1L), previously associated with oblique facial clefting and Opitz G/BBB syndrome. The first patient and his affected mother were previously-reported by Hoffman et al. in this journal as a new syndrome resembling Teebi hypertelorism and Aarskog syndromes in 2007. This patient had hypertelorism, sagittal and coronal craniosynostosis, ptosis, natal teeth, unusual umbilicus, shawl scrotum, small hands, and feet, with grossly normal development. Our second patient had classic Teebi hypertelorism syndrome with hypertelorism and a giant umbilical hernia. Patient one and his affected mother had a c.1260G>C:p.E420D variant and patient two had a de novo c.1198_1203delATACAC:p.I400_H401del variant in SPECC1L. We review the phenotypic findings in the previously-published Teebi hypertelorism syndrome patients, and the Opitz G/BBB patients with SPECC1L mutations. In addition we emphasize the findings of aortic root dilation and craniosynostosis in these patients, which should be considered in their management.
Subject(s)
Hypertelorism/genetics , Mutation/genetics , Phosphoproteins/genetics , Abnormalities, Multiple , Adolescent , Base Sequence , Child , Child, Preschool , Craniofacial Abnormalities , DNA Mutational Analysis , Facies , Family , Foot Deformities, Congenital , Hand Deformities, Congenital , Humans , Infant , Infant, Newborn , Male , Molecular Sequence Data , PhenotypeABSTRACT
Common copy number variations (CNVs) represent a significant source of genetic diversity, yet their influence on phenotypic variability, including disease susceptibility, remains poorly understood. To address this problem in human cancer, we performed a genome-wide association study of CNVs in the childhood cancer neuroblastoma, a disease in which single nucleotide polymorphism variations are known to influence susceptibility. We first genotyped 846 Caucasian neuroblastoma patients and 803 healthy Caucasian controls at approximately 550,000 single nucleotide polymorphisms, and performed a CNV-based test for association. We then replicated significant observations in two independent sample sets comprised of a total of 595 cases and 3,357 controls. Here we describe the identification of a common CNV at chromosome 1q21.1 associated with neuroblastoma in the discovery set, which was confirmed in both replication sets. This CNV was validated by quantitative polymerase chain reaction, fluorescent in situ hybridization and analysis of matched tumour specimens, and was shown to be heritable in an independent set of 713 cancer-free parent-offspring trios. We identified a previously unknown transcript within the CNV that showed high sequence similarity to several neuroblastoma breakpoint family (NBPF) genes and represents a new member of this gene family (NBPF23). This transcript was preferentially expressed in fetal brain and fetal sympathetic nervous tissues, and the expression level was strictly correlated with CNV state in neuroblastoma cells. These data demonstrate that inherited copy number variation at 1q21.1 is associated with neuroblastoma and implicate a previously unknown neuroblastoma breakpoint family gene in early tumorigenesis of this childhood cancer.