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Rationale: Despite the increased recognition of TBX4 (T-BOX transcription factor 4)-associated pulmonary arterial hypertension (PAH), genotype-phenotype associations are lacking and may provide important insights.Objectives: To compile and functionally characterize all TBX4 variants reported to date and undertake a comprehensive genotype-phenotype analysis.Methods: We assembled a multicenter cohort of 137 patients harboring monoallelic TBX4 variants and assessed the pathogenicity of missense variation (n = 42) using a novel luciferase reporter assay containing T-BOX binding motifs. We sought genotype-phenotype correlations and undertook a comparative analysis with patients with PAH with BMPR2 (Bone Morphogenetic Protein Receptor type 2) causal variants (n = 162) or no identified variants in PAH-associated genes (n = 741) genotyped via the National Institute for Health Research BioResource-Rare Diseases.Measurements and Main Results: Functional assessment of TBX4 missense variants led to the novel finding of gain-of-functio effects associated with older age at diagnosis of lung disease compared with loss-of-function effects (P = 0.038). Variants located in the T-BOX and nuclear localization domains were associated with earlier presentation (P = 0.005) and increased incidence of interstitial lung disease (P = 0.003). Event-free survival (death or transplantation) was shorter in the T-BOX group (P = 0.022), although age had a significant effect in the hazard model (P = 0.0461). Carriers of TBX4 variants were diagnosed at a younger age (P, 0.001) and had worse baseline lung function (FEV1, FVC) (P = 0.009) than the BMPR2 and no identified causal variant groups.Conclusions: We demonstrated that TBX4 syndrome is not strictly the result of haploinsufficiency but can also be caused by gain of function. The pleiotropic effects of TBX4 in lung disease may be in part explained by the differential effect of pathogenic mutations located in critical protein domains.

Idiopathic pulmonary arterial hypertension (IPAH) is a rare but fatal disease diagnosed by right heart catheterisation and the exclusion of other forms of pulmonary arterial hypertension, producing a heterogeneous population with varied treatment response. Here we show unsupervised machine learning identification of three major patient subgroups that account for 92% of the cohort, each with unique whole blood transcriptomic and clinical feature signatures. These subgroups are associated with poor, moderate, and good prognosis. The poor prognosis subgroup is associated with upregulation of the ALAS2 and downregulation of several immunoglobulin genes, while the good prognosis subgroup is defined by upregulation of the bone morphogenetic protein signalling regulator NOG, and the C/C variant of HLA-DPA1/DPB1 (independently associated with survival). These findings independently validated provide evidence for the existence of 3 major subgroups (endophenotypes) within the IPAH classification, could improve risk stratification and provide molecular insights into the pathogenesis of IPAH.

Rationale: Idiopathic and heritable pulmonary arterial hypertension (PAH) are rare but comprise a genetically heterogeneous patient group. RNA sequencing linked to the underlying genetic architecture can be used to better understand the underlying pathology by identifying key signaling pathways and stratify patients more robustly according to clinical risk.Objectives: To use a three-stage design of RNA discovery, RNA validation and model construction, and model validation to define a set of PAH-associated RNAs and a single summarizing RNA model score. To define genes most likely to be involved in disease development, we performed Mendelian randomization (MR) analysis.Methods: RNA sequencing was performed on whole-blood samples from 359 patients with idiopathic, heritable, and drug-induced PAH and 72 age- and sex-matched healthy volunteers. The score was evaluated against disease severity markers including survival analysis using all-cause mortality from diagnosis. MR used known expression quantitative trait loci and summary statistics from a PAH genome-wide association study.Measurements and Main Results: We identified 507 genes with differential RNA expression in patients with PAH compared with control subjects. A model of 25 RNAs distinguished PAH with 87% accuracy (area under the curve 95% confidence interval: 0.791-0.945) in model validation. The RNA model score was associated with disease severity and long-term survival (P = 4.66 × 10-6) in PAH. MR detected an association between SMAD5 levels and PAH disease susceptibility (odds ratio, 0.317; 95% confidence interval, 0.129-0.776; P = 0.012).Conclusions: A whole-blood RNA signature of PAH, which includes RNAs relevant to disease pathogenesis, associates with disease severity and identifies patients with poor clinical outcomes. Genetic variants associated with lower SMAD5 expression may increase susceptibility to PAH.

The Ensembl project (http://www.ensembl.org) is a comprehensive genome information system featuring an integrated set of genome annotation, databases and other information for chordate and selected model organism and disease vector genomes. As of release 47 (October 2007), Ensembl fully supports 35 species, with preliminary support for six additional species. New species in the past year include platypus and horse. Major additions and improvements to Ensembl since our previous report include extensive support for functional genomics data in the form of a specialized functional genomics database, genome-wide maps of protein-DNA interactions and the Ensembl regulatory build; support for customization of the Ensembl web interface through the addition of user accounts and user groups; and increased support for genome resequencing. We have also introduced new comparative genomics-based data mining options and report on the continued development of our software infrastructure.

Pulmonary arterial hypertension (PAH) is a rare disease that leads to premature death from right heart failure. It is strongly associated with elevated red cell distribution width (RDW), a correlate of several iron status biomarkers. High RDW values can signal early stage iron deficiency or iron deficiency anaemia. This study investigated if elevated RDW is causally associated with PAH.A two-sample Mendelian randomisation (MR) approach was applied to investigate whether genetic predisposition to higher levels of RDW increases the odds of developing PAH. Primary and secondary MR analyses were performed using all available genome-wide significant RDW variants (n=179) and five genome-wide significant RDW variants that act via systemic iron status, respectively.We confirmed the observed association between RDW and PAH (OR=1.90, 95% CI=1.80-2.01) in a multi-centre case-control study (N cases=642, N disease controls=15 889). The primary MR analysis was adequately powered to detect a causal effect (OR) from between 1.25 and 1.52 or greater based on estimates reported in the RDW GWAS or from our own data. There was no evidence for a causal association between RDW and PAH in either the primary (ORcausal=1.07, 95% CI=0.92-1.24) or the secondary (ORcausal=1.09, 95% CI=0.77-1.54) MR analysis.The results suggest that at least some of the observed association of RDW with PAH is secondary to disease progression. Results of iron therapeutic trials in PAH should be interpreted with caution as any improvements observed may not be mechanistically linked to the development of PAH.

Background Raregenetic variantscause pulmonary arterial hypertension, but the contribution of commongenetic variationto disease risk and natural history is poorly characterised. We tested for genome-wide association for pulmonary arterial hypertension in large international cohorts and assessed the contribution of associated regions to outcomes. Methods We did two separate genome-wide association studies (GWAS) and a meta-analysis of pulmonary arterial hypertension. These GWAS used data from four international case-control studies across 11 744 individuals with European ancestry (including 2085 patients). One GWAS usedgenotypesfrom 5895 whole-genome sequences and the other GWAS used genotyping array data from an additional 5849 individuals.Cross-validationof loci reaching genome-wide significance was sought by meta-analysis. Conditional analysis corrected for the most significant variants at each locus was used to resolve signals for multiple associations. We functionally annotated associated variants and tested associations with duration ofsurvival.All-cause mortalitywas the primary endpoint in survival analyses. Findings A locus nearSOX17(rs10103692, odds ratio 1·80 [95% CI 1·55–2·08], p=5·13 × 10–15) and a second locus inHLA-DPA1andHLA-DPB1(collectively referred to asHLA-DPA1/DPB1here; rs2856830, 1·56 [1·42–1·71], p=7·65 × 10–20) within the class II MHC region were associated with pulmonary arterial hypertension. TheSOX17locus had two independent signals associated with pulmonary arterial hypertension (rs13266183, 1·36 [1·25–1·48], p=1·69 × 10–12; and rs10103692). Functional andepigenomicdata indicate that the risk variants nearSOX17altergene regulationvia anenhanceractive inendothelial cells. Pulmonary arterial hypertension risk variants determined haplotype-specific enhancer activity, and CRISPR-mediated inhibition of the enhancer reducedSOX17expression. TheHLA-DPA1/DPB1rs2856830 genotype was strongly associated with survival. Median survival fromdiagnosisin patients with pulmonary arterial hypertension with the C/C homozygous genotype was double (13·50 years [95% CI 12·07 to >13·50]) that of those with the T/T genotype (6·97 years [6·02–8·05]), despite similar baselinedisease severity. Interpretation This is the first study to report that common genetic variation at loci in an enhancer nearSOX17and inHLA-DPA1/DPB1is associated with pulmonary arterial hypertension. Impairment of SOX17 function might be more common in pulmonary arterial hypertension than suggested by raremutationsinSOX17. Further studies are needed to confirm the association betweenHLA typingor rs2856830 genotyping and survival, and to determine whether HLA typing or rs2856830 genotyping improvesrisk stratificationin clinical practice or trials.

Multiple primary tumors (MPTs) affect a substantial proportion of cancer survivors and can result from various causes, including inherited predisposition. Currently, germline genetic testing of MPT-affected individuals for variants in cancer-predisposition genes (CPGs) is mostly targeted by tumor type. We ascertained pre-assessed MPT individuals (with at least two primary tumors by age 60 years or at least three by 70 years) from genetics centers and performed whole-genome sequencing (WGS) on 460 individuals from 440 families. Despite previous negative genetic assessment and molecular investigations, pathogenic variants in moderate- and high-risk CPGs were detected in 67/440 (15.2%) probands. WGS detected variants that would not be (or were not) detected by targeted resequencing strategies, including low-frequency structural variants (6/440 [1.4%] probands). In most individuals with a germline variant assessed as pathogenic or likely pathogenic (P/LP), at least one of their tumor types was characteristic of variants in the relevant CPG. However, in 29 probands (42.2% of those with a P/LP variant), the tumor phenotype appeared discordant. The frequency of individuals with truncating or splice-site CPG variants and at least one discordant tumor type was significantly higher than in a control population (χ2 = 43.642; p ≤ 0.0001). 2/67 (3%) probands with P/LP variants had evidence of multiple inherited neoplasia allele syndrome (MINAS) with deleterious variants in two CPGs. Together with variant detection rates from a previous series of similarly ascertained MPT-affected individuals, the present results suggest that first-line comprehensive CPG analysis in an MPT cohort referred to clinical genetics services would detect a deleterious variant in about a third of individuals.

Background Rare genetic variants cause pulmonary arterial hypertension, but the contribution of common genetic variation to disease risk and natural history is poorly characterised. We tested for genome-wide association for pulmonary arterial hypertension in large international cohorts and assessed the contribution of associated regions to outcomes. Methods We did two separate genome-wide association studies (GWAS) and a meta-analysis of pulmonary arterial hypertension. These GWAS used data from four international case-control studies across 11 744 individuals with European ancestry (including 2085 patients). One GWAS used genotypes from 5895 whole-genome sequences and the other GWAS used genotyping array data from an additional 5849 individuals. Cross-validation of loci reaching genome-wide significance was sought by meta-analysis. Conditional analysis corrected for the most significant variants at each locus was used to resolve signals for multiple associations. We functionally annotated associated variants and tested associations with duration of survival. All-cause mortality was the primary endpoint in survival analyses. Findings A locus near SOX17 (rs10103692, odds ratio 1·80 [95% CI 1·55–2·08], p=5·13 × 10–15) and a second locus in HLA-DPA1 and HLA-DPB1 (collectively referred to as HLA-DPA1/DPB1 here; rs2856830, 1·56 [1·42–1·71], p=7·65 × 10–20) within the class II MHC region were associated with pulmonary arterial hypertension. The SOX17 locus had two independent signals associated with pulmonary arterial hypertension (rs13266183, 1·36 [1·25–1·48], p=1·69 × 10–12; and rs10103692). Functional and epigenomic data indicate that the risk variants near SOX17 alter gene regulation via an enhancer active in endothelial cells. Pulmonary arterial hypertension risk variants determined haplotype-specific enhancer activity, and CRISPR-mediated inhibition of the enhancer reduced SOX17 expression. The HLA-DPA1/DPB1 rs2856830 genotype was strongly associated with survival. Median survival from diagnosis in patients with pulmonary arterial hypertension with the C/C homozygous genotype was double (13·50 years [95% CI 12·07 to >13·50]) that of those with the T/T genotype (6·97 years [6·02–8·05]), despite similar baseline disease severity. Interpretation This is the first study to report that common genetic variation at loci in an enhancer near SOX17 and in HLA-DPA1/DPB1 is associated with pulmonary arterial hypertension. Impairment of SOX17 function might be more common in pulmonary arterial hypertension than suggested by rare mutations in SOX17. Further studies are needed to confirm the association between HLA typing or rs2856830 genotyping and survival, and to determine whether HLA typing or rs2856830 genotyping improves risk stratification in clinical practice or trials.

wird nachgereicht

Supplemental Digital Content is available in the text., Background: Pulmonary arterial hypertension (PAH) is a heterogeneous disorder with high mortality. Methods: We conducted a comprehensive study of plasma metabolites using ultraperformance liquid chromatography mass spectrometry to identify patients at high risk of early death, to identify patients who respond well to treatment, and to provide novel molecular insights into disease pathogenesis. Results: Fifty-three circulating metabolites distinguished well-phenotyped patients with idiopathic or heritable PAH (n=365) from healthy control subjects (n=121) after correction for multiple testing (P

International audience; The Ensembl project (http://www.ensembl.org) is a comprehensive genome information system featuring an integrated set of genome annotation, databases and other information for chordate and selected model organism and disease vector genomes. As of release 47 (October 2007), Ensembl fully supports 35 species, with preliminary support for six additional species. New species in the past year include platypus and horse. Major additions and improvements to Ensembl since our previous report include extensive support for functional genomics data in the form of a specialized functional genomics database, genome-wide maps of protein–DNA interactions and the Ensembl regulatory build; support for customization of the Ensembl web interface through the addition of user accounts and user groups; and increased support for genome resequencing. We have also introduced new comparative genomics-based data mining options and report on the continued development of our software infrastructure.

Ziel/Aim: Using F-18-A85380 (2FA) PET we recently demonstrated significant cerebral nAChR declines in early AD which correlated significantly with the loss of cognitive function (1-2). However, 2FA is not well suited in clinical routine use because of slow kinetics, acquisition times up to 7 hours, and limited nAChR selectivity. Thus, we developed the new tracer F-18-Flubatine, an epibatidine derivative without toxicity in humans formerly named as F-18-NCFHEB (3) and report here on the worldwide first human Flubatine-PET results. Methodik/Methods: 16 mild AD patients (NINCDS-ADRDA, age 74.4±6.6, MMSE 23.7±2.8) and 11 age-matched healthy controls (HCs, MMSE 28.5±0.9), all nonsmokers and nave for central acting medication, underwent Flubatine-PET (370 MBq, 3D-acquisition, ECAT Exact HR+). Dynamic 0-270min p.i. scans were acquired and corrected for motion (SPM2). Kinetic modeling was applied to 29 brain VOI-based tissue-activity curves (VOIs defined on individual MRI) using a one-tissue compartment model with measured arterial input function. Total distribution volume (DV) and binding potential (BP, reference region: corpus callosum) were used to characterize specific binding. Ergebnisse/Results: Image quality of Flubatine scans was clearly superior to 2FA, and a 20 minutes scan already adequate for visual analysis. All 29 regions were well described with one-tissue compartment. PET data acquired over only 90 minutes were sufficient to estimate all kinetic parameters precisely indicating a fast receptor binding kinetic (much faster than for 2FA). DVs in HCs increase as expected with receptor density: Corpus callosum (DV: 4.81±0.32), posterior cingulate (8.92±0.66), temporal (9.03±0.44), pons (11.00±1.19), thalamus (24.32±2.96). The AD patients showed extensive BP reductions in frontal, parietal, temporal, anterior and posterior cingulate cortices, caudate, and midbrain (all p 0.41). Schlussfolgerungen/Conclusions: Due to the significant shorter acquisition time and superior image quality Flubatine appears to be a much more valuable tracer than 2FA to image nAChRs in humans. Early AD patients show significant declines of nAChRs in brain regions typically affected by AD pathology which correlate well with the corresponding cognitive declines. These results indicate that Flubatine-PET has a great potential as a biomarker for early AD diagnosis. Literatur/References: (1) Sabri et al. Eur J Nucl Med Mol Imaging 2008; 35 (Suppl. 1): 30-45(2) Kendziorra et al., Eur J Nucl Med Mol Imaging 2011; 38: 515-525(3) Brust et al. Synapse 2008; 62: 205-218This trial is granted by the German Federal Ministry of Education and Research (BMBF-Nr. 01EZ0820)

Using 2-[18F]F-A85380 (2FA) PET we recently demonstrated significant cerebral nAChR declines in early AD which correlated significantly with the loss of cognitive function [1]. However, 2FA is not well suited in routine use because of slow kinetics, acquisition times up to 7 hours, and limited nAChR selectivity. Thus, we developed the new tracer NCFHEB [2] and report here on the worldwide first human NCFHEB-PET results. 6 mild AD patients (NINCDS-ADRDA, age 76.7±5.9, MMSE 23.8±3.0) and 5 age-matched healthy controls (HCs, MMSE 28.4±1.1), all nonsmokers and naïve for central acting medication, underwent NCFHEB-PET (370 MBq, 3D-acquisition, ECAT Exact HR+). Dynamic 0-270min p.i. scans were acquired and corrected for motion (SPM2). Kinetic modeling was applied to 29 brain VOI-based tissue-activity curves (VOIs defined on individual MRI) using a one-tissue compartment model with measured arterial input function. Total distribution volume (DV) and binding potential (BP, reference region: corpus callosum) were used to characterize specific binding. Image quality of NCFHEB scans was clearly superior to 2FA, and a 20 minutes scan already adequate for visual analysis. All 29 regions were well described with one-tissue compartment. PET data acquired over only 90 minutes were sufficient to estimate all kinetic parameters precisely indicating a fast receptor binding kinetic (much faster than for 2FA). DVs in HCs increase as expected with receptor density: Corpus callosum (DV: 4.81±0.32), posterior cingulate (8.92±0.66), temporal (9.03±0.44), pons (11.00±1.19), thalamus (24.32±2.96). The AD patients showed extensive BP reductions in frontal, parietal, temporal, anterior and posterior cingulate cortices, caudate, and hippocampus (all p

Ziel/Aim: (-)-F18-Norchloro-fluoro-homoepibatidin ((-)-F18-NCFHEB) ist ein neuer und vielversprechender Radioligand für die Darstellung von alpha4beta2 nikotinischen Acetylcholinrezeptoren mit PET. Um das Strahlenrisikio durch diesen Tracer abzuschätzen, wurden die resultierenden Organdosen (OD) und die effektive Dosis (ED) im Rahmen einer Machbarkeitsstudie inkorporationsdosimetrisch ermittelt. Methodik/Methods: Die inkorporationsdosimetrische Untersuchung von (-)-F18-NCFHEB wurde an 3 Probanden (2 männlich, 1 weiblich; Alter: 59,6±3,9a; Gewicht: 74,3±3,1Kg) vorgenommen. Die Probanden unterzogen sich nach intravenöser Injektion von 353,7±10,2 MBq (-)-F18-NCFHEB einer sequentiellen PET-CT-Untersuchung bis zu 7h nach Injektion an einem SIEMENS Biograph16 PET-CT-System (9 Bettpositionen pro Frame, 1,5-6min/Bettposition, CT-Schwächungskorrektur, iterative Rekonstruktion). Bis zu 7h p.i. wurde sämtlicher Urin gesammelt und dessen Aktivitätskonzentration bestimmt. Alle den Tracer aufnehmenden Organe wurden CT-geführt mit dreidimensionalen Regionen (VOIs) markiert, und ihr Aktivitätsinhalt als Zeit-Aktivitäts-Verlauf dargestellt. Mit dem EXM-Modul von OLINDA [1] wurden Zeit-Aktivitäts-Kurven an diese Daten angepasst. Der Aktivitätsverlauf in der Blase wurde anhand der Urinabgaben bestimmt. ODs wurden unter Verwendung des 73,7kg-"adult male model" mit OLINDA bestimmt. Die ED wurde unter Verwendung der Gewebewichtungsfaktoren in der ICRP 103 von 2007 berechnet [2]. Ergebnisse/Results: Die Harnblaseblase erhält die höchste OD (80,2±37,8µSv/MBq), gefolgt von der Leber (44,7±5,4µSv/MBq), den Nieren (38,6±5,1µSv/MBq), der Milz (38,4±11,6µSv/MBq), der Schilddrüse (32,8±11,9µSv/MBq) und den Lungen (31,1±5,3µSv/MBq). Die höchsten Beiträge zur ED leisten die Lunge (3,7±0,6µSv/MBq), die Harnblase (3,2±1,5µSv/MBq), der Magen (2,9±0,7µSv/MBq), das rote KM (2,3±0,2µSv/MBq), der absteigende Dickdarm (1,9±0,2µSv/MBq) und die Leber (1,8±0,2µSv/MBq). Die ED durch i.v. Applikation von (-)-F18-NCFHEB ergibt sich zu 22,9±0,7µSv/MBq. Schlussfolgerungen/Conclusions: Die effektive Dosis als Maß für das summarische Risiko durch i.v. Applikation von 300 MBq (-)-F18-NCFHEB) ergibt sich zu 6,8±0,2mSv. Dies liegt im Bereich der Strahlenexposition durch andere F18-markierte Radioliganden. Diese günstigen dosimetrischen Ergebnisse unterstützen die weitere Entwicklung von (-)-F18-NCFHEB) als klinischen Hirn-PET-Tracer. Literatur/References: [1] Stabin et. al.: OLINDA/EXM: The Second-Generation Personal Computer Software for Internal Dose Assessment in Nuclear Medicine; JNM 46/6, 2005 [2] International Commission on Radiological Protection. Recommendations of the International Commission on Radiological Protection. ICRP Publication 103, Pergamon Press, New York, 2007 Die Studie wird vom Bundesministerium für Bildung und Forschung gefördert (Nr. 01EZ0820)

The Ensembl project (http://www.ensembl.org) is a comprehensive genome information system featuring an integrated set of genome annotation, databases and other information for chordate and selected model organism and disease vector genomes. As of release 47 (October 2007), Ensembl fully supports 35 species, with preliminary support for six additional species. New species in the past year include platypus and horse. Major additions and improvements to Ensembl since our previous report include extensive support for functional genomics data in the form of a specialized functional genomics database, genome-wide maps of protein-DNA interactions and the Ensembl regulatory build; support for customization of the Ensembl web interface through the addition of user accounts and user groups; and increased support for genome resequencing. We have also introduced new comparative genomics-based data mining options and report on the continued development of our software infrastructure.