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BACKGROUND & AIMS: Anti-tumor necrosis factor (anti-TNF) therapies are commonly prescribed treatments for Crohn's Disease (CD) and Ulcerative Colitis (UC). Many patients treated with anti-TNF therapy eventually develop anti-drug antibodies (ADA). Understanding the factors associated with immunogenicity in anti-TNF treated patients can help guide treatment. The Humira SERENE studies were phase 3 trials studying adalimumab induction regimens in CD and UC patients. METHODS: We imputed alleles for 7 HLA genes in 1100 patients from the SERENE CD and SERENE UC trials. We tested these alleles for association with time to immunogenicity. We then tested loci significantly associated with immunogenicity for association with patients that had consistently low drug-serum concentrations. RESULTS: This study replicated the association of HLA-DQA1*05 with time to immunogenicity (Hazard Ratio (HR) 1.42, P=2.22E-06). Specifically, HLA-DQA1*05:05 was strongly associated (HR 1.76, P=2.02E-10) and we detected a novel association represented by HLA-DRB1*01:02 (HR 3.16, P=2.92E-07). Carriage of HLA-DQA1*05:05 and HLA-DRB1*01:02 were both associated with patients who experienced consistently low adalimumab trough concentrations (HLA-DQA1*05:05 OR 1.98, P=0.0049; HLA DRB1*01:02 OR 7.06, P=7.44E-05). CONCLUSIONS: We found a significant association between alleles at genes in the human HLA locus and the formation of adalimumab immunogenicity and low adalimumab drug-serum concentrations in large clinical studies of CD and UC patients. This work extends previous results in Crohn's disease to ulcerative colitis and directly shows a genetic association in patients with low drug concentrations. This work builds on existing literature to suggest genetic screening as a useful tool for clinicians concerned with patient anti-TNF immunogenicity.
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Importance: The involvement of chronic inflammation in the pathogenesis of age-related macular degeneration (AMD) opens therapeutic possibilities to AMD management. Objective: To determine whether Janus kinase inhibitors (JAKis) are associated with a reduced risk of AMD development in patients with autoimmune diseases. Design, Setting, and Participants: This retrospective observational cohort study used administrative claims data from Merative MarketScan research databases (Commercial and Medicare Supplemental) and Optum Clinformatics Data Mart databases between January 1, 2010, and January 31, 2022. Patients with autoimmune diseases satisfying study eligibility criteria and who received JAKi treatment (9126 in MarketScan and 5667 in Optum) were propensity score matched (1:1) to identical numbers of study-eligible patients who received non-JAKi-based immunotherapy. Exposure: Treatment duration of 6 months or longer. Main Outcomes and Measures: Incidence rates of AMD (exudative and nonexudative) over the first 6 to 18 months of treatment were determined, and bayesian Poisson regression models were used to estimate incidence rate ratios, 95% CIs, and posterior probabilities of AMD. Results: After matching, female sex represented the majority of the patient population in both MarketScan and Optum (14â¯019/18â¯252 [76.6%] and 8563/3364 [75.2%], respectively in the JAKi patient population). More than 60% of the patient population was older than 55 years of age in both cohorts. Over the specified treatment period, a 49% relative reduction in incidence of AMD was observed among patients who received JAKi therapy (10/9126 events; adjusted incidence rate ratio [AIRR], 0.51; 95% CI, 0.19-0.90) vs those who received non-JAKi therapy (43/9126 events; AIRR, 1 [reference]) in MarketScan, and a 73% relative reduction in incidence of AMD was observed among patients who received JAKi therapy (3/5667 events; AIRR, 0.27; 95% CI, 0.03-0.74) vs those who received non-JAKi therapy (21/5667 events; AIRR, 1 [reference]) in Optum. The absolute percentage reductions were 0.36% (MarketScan) and 0.32% (Optum), favoring patients who received JAKi therapy. Posterior probabilities of the adjusted risk being less than unity were 97.6% (MarketScan) and 98.9% (Optum) for those who received JAKi therapy vs those who received non-JAKi therapy in MarketScan and Optum, respectively. Conclusions and Relevance: JAKi use may be associated with a reduced risk of incident AMD in US adults with major autoimmune diseases. The absolute percentage reduction is consistent with a potential role for JAKi in this population. Future studies with long-term follow-up are recommended to investigate the association between JAKi use and incident AMD in other disease indications. Investigation into the role of systemic inflammation and JAK-signal transducers and activators of transcription signaling in AMD may improve understanding of the pathophysiology of AMD and lead to new treatment options.
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Doenças Autoimunes , Inibidores de Janus Quinases , Degeneração Macular , Humanos , Feminino , Masculino , Estudos Retrospectivos , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/epidemiologia , Idoso , Incidência , Pessoa de Meia-Idade , Inibidores de Janus Quinases/uso terapêutico , Degeneração Macular/tratamento farmacológico , Degeneração Macular/epidemiologia , Degeneração Macular/diagnóstico , Estados Unidos/epidemiologia , Fatores de Risco , Idoso de 80 Anos ou mais , Bases de Dados FactuaisRESUMO
BACKGROUND AND AIMS: Anti-tumour necrosis factor [anti-TNF] therapy is widely used for the treatment of inflammatory bowel disease, yet many patients are primary non-responders, failing to respond to induction therapy. We aimed to identify blood gene expression differences between primary responders and primary non-responders to anti-TNF monoclonal antibodies [infliximab and adalimumab], and to predict response status from blood gene expression and clinical data. METHODS: The Personalised Anti-TNF Therapy in Crohn's Disease [PANTS] study is a UK-wide prospective observational cohort study of anti-TNF therapy outcome in anti-TNF-naive Crohn's disease patients [ClinicalTrials.gov identifier: NCT03088449]. Blood gene expression in 324 unique patients was measured by RNA-sequencing at baseline [week 0], and at weeks 14, 30, and 54 after treatment initiation [total sample sizeâ =â 814]. RESULTS: After adjusting for clinical covariates and estimated blood cell composition, baseline expression of major histocompatibility complex, antigen presentation, myeloid cell enriched receptor, and other innate immune gene modules was significantly higher in anti-TNF responders vs non-responders. Expression changes from baseline to week 14 were generally of consistent direction but greater magnitude [i.e. amplified] in responders, but interferon-related genes were upregulated uniquely in non-responders. Expression differences between responders and non-responders observed at week 14 were maintained at weeks 30 and 54. Prediction of response status from baseline clinical data, cell composition, and module expression was poor. CONCLUSIONS: Baseline gene module expression was associated with primary response to anti-TNF therapy in PANTS patients. However, these baseline expression differences did not predict response with sufficient sensitivity for clinical use.
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Doença de Crohn , Humanos , Doença de Crohn/tratamento farmacológico , Doença de Crohn/genética , Redes Reguladoras de Genes , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Estudos Prospectivos , Imunoterapia , Fator de Necrose Tumoral alfaRESUMO
BACKGROUND AND AIMS: This study assessed whether baseline triggering receptor expressed on myeloid cells [TREM-1] whole blood gene expression predicts response to anti-TNF therapy in patients with UC or CD. METHODS: TREM-1 whole blood gene expression was analysed by RNA sequencing [RNA-seq] in patients with moderately to severely active UC or CD treated with adalimumab in the Phase 3 SERENE-UC and SERENE-CD clinical trials. The predictive value of baseline TREM-1 expression was evaluated and compared according to endoscopic and clinical response vs non-response, and remission vs non-remission, at Weeks 8 and 52 [SERENE-UC], and Weeks 12 and 56 [SERENE-CD]. RESULTS: TREM-1 expression was analysed in 95 and 106 patients with UC and CD, respectively, receiving standard-dose adalimumab induction treatment. In SERENE-UC, baseline TREM-1 expression was not predictive of endoscopic response [p=0.48], endoscopic remission [p=0.53], clinical response [p=0.58] or clinical remission [p=0.79] at Week 8, or clinical response [p=0.60] at Week 52. However, an association was observed with endoscopic response [p=0.01], endoscopic remission [p=0.048], and clinical remission [p=0.04997] at Week 52. For SERENE-CD, baseline TREM-1 expression was not predictive of endoscopic response [p=0.56], endoscopic remission [p=0.33], clinical response [p=0.07], clinical remission [p=0.65] at Week 12, or endoscopic response [p=0.61], endoscopic remission [p=0.51], clinical response [p=0.62] or clinical remission [p=0.97] at Week 56. CONCLUSIONS: Baseline TREM-1 gene expression did not uniformly predict adalimumab response in SERENE clinical trials. Further research is needed to identify potential blood-based biomarkers predictive of response to anti-TNF therapy in patients with IBD.
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BACKGROUND AND AIMS: Anti-TNF treatment failure in patients with inflammatory bowel disease (IBD) is common and frequently related to low drug concentrations. In order to identify patients who may benefit from dose optimisation at the outset of anti-TNF therapy, we sought to define epigenetic biomarkers in whole blood at baseline associated with anti-TNF drug concentrations at week 14. METHODS: DNA methylation from 1,104 whole blood samples from 385 patients in the Personalised Anti-TNF Therapy in Crohn's disease (PANTS) study were assessed using the Illumina EPIC Beadchip (v1.0) at baseline, weeks 14, 30 and 54. We compared DNA methylation profiles in anti-TNF-treated patients who experienced primary non-response at week 14 and if they were assessed at subsequent time points, were not in remission at week 30 or 54 (infliximab n = 99, adalimumab n = 94), with patients who responded at week 14 and when assessed at subsequent time points, were in remission at week 30 or 54 (infliximab n = 99, adalimumab n = 93). RESULTS: Overall, between baseline and week 14, we observed 4,999 differentially methylated probes (DMPs) annotated to 2376 genes following anti-TNF treatment. Pathway analysis identified 108 significant gene ontology terms enriched in biological processes related to immune system processes and responses.Epigenome-wide association (EWAS) analysis identified 323 DMPs annotated to 210 genes at baseline associated with higher anti-TNF drug concentrations at week 14. Of these, 125 DMPs demonstrated shared associations with other common traits (proportion of shared CpGs compared to DMPs) including body mass index (23.2%), followed by CRP (11.5%), smoking (7.4%), alcohol consumption per day (7.1%) and IBD type (6.8%). EWAS of primary non-response to anti-TNF identified 20 DMPs that were associated with both anti-TNF drug concentration and primary non-response to anti-TNF with a strong correlation of the coefficients (Spearman's rho = -0.94, p < 0.001). CONCLUSION: Baseline DNA methylation profiles may be used as a predictor for anti-TNF drug concentration at week 14 to identify patients who may benefit from dose optimisation at the outset of anti-TNF therapy.
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PURPOSE: We report the diagnostic yield of whole-exome sequencing (WES) in 3,040 consecutive cases at a single clinical laboratory. METHODS: WES was performed for many different clinical indications and included the proband plus two or more family members in 76% of cases. RESULTS: The overall diagnostic yield of WES was 28.8%. The diagnostic yield was 23.6% in proband-only cases and 31.0% when three family members were analyzed. The highest yield was for patients who had disorders involving hearing (55%, N = 11), vision (47%, N = 60), the skeletal muscle system (40%, N = 43), the skeletal system (39%, N = 54), multiple congenital anomalies (36%, N = 729), skin (32%, N = 31), the central nervous system (31%, N = 1,082), and the cardiovascular system (28%, N = 54). Of 2,091 cases in which secondary findings were analyzed for 56 American College of Medical Genetics and Genomics-recommended genes, 6.2% (N = 129) had reportable pathogenic variants. In addition to cases with a definitive diagnosis, in 24.2% of cases a candidate gene was reported that may later be reclassified as being associated with a definitive diagnosis. CONCLUSION: Our experience with our first 3,040 WES cases suggests that analysis of trios significantly improves the diagnostic yield compared with proband-only testing for genetically heterogeneous disorders and facilitates identification of novel candidate genes.Genet Med 18 7, 696-704.
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Doenças Genéticas Inatas/genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Exoma/genética , Doenças Genéticas Inatas/classificação , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/epidemiologia , Humanos , Mutação , Análise de Sequência de DNA/métodosRESUMO
OBJECTIVE: To determine the cause and course of a novel syndrome with progressive encephalopathy and brain atrophy in children. METHODS: Clinical whole-exome sequencing was performed for global developmental delay and intellectual disability; some patients also had spastic paraparesis and evidence of clinical regression. Six patients were identified with de novo missense mutations in the kinesin gene KIF1A. The predicted functional disruption of these mutations was assessed in silico to compare the calculated conformational flexibility and estimated efficiency of ATP binding to kinesin motor domains of wild-type (WT) versus mutant alleles. Additionally, an in vitro microtubule gliding assay was performed to assess the effects of de novo dominant, inherited recessive, and polymorphic variants on KIF1A motor function. RESULTS: All six subjects had severe developmental delay, hypotonia, and varying degrees of hyperreflexia and spastic paraparesis. Microcephaly, cortical visual impairment, optic neuropathy, peripheral neuropathy, ataxia, epilepsy, and movement disorders were also observed. All six patients had a degenerative neurologic course with progressive cerebral and cerebellar atrophy seen on sequential magnetic resonance imaging scans. Computational modeling of mutant protein structures when compared to WT kinesin showed substantial differences in conformational flexibility and ATP-binding efficiency. The de novo KIF1A mutants were nonmotile in the microtubule gliding assay. INTERPRETATION: De novo mutations in KIF1A cause a degenerative neurologic syndrome with brain atrophy. Computational and in vitro assays differentiate the severity of dominant de novo heterozygous versus inherited recessive KIF1A mutations. The profound effect de novo mutations have on axonal transport is likely related to the cause of progressive neurologic impairment in these patients.
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PURPOSE: To describe the clinical, functional, and genetic findings in a young Caucasian girl and her father, in whom a mutation of the PAX6 gene was identified. METHODS: Detailed histories, eye examinations, and flash electroretinograms (ERGs) were acquired from both patients, and molecular genetic diagnostic testing was performed. Both patients were followed over a 2-year period. RESULTS: At presentation, the proband displayed congenital nystagmus, photophobia, posterior embryotoxon, foveal hypoplasia, and coarse peripheral retinal pigment epithelium mottling. Light-adapted cone-driven ERG responses were delayed and reduced. The father had similar findings, but additionally displayed corneal clouding and pannus, decreased best-corrected visual acuity, and his ERG demonstrated a larger reduction in ERG cone-driven responses. PAX6 testing of the proband revealed a heterozygous mutation in exon 13 resulting in a p.X423Lfs (p.Stop423Leufs) frameshift amino acid substitution, predicting aberrant protein elongation by either 14 or 36 amino acids (p.X423Lext14 or p.X423Lext36) and subsequent disruption of normal protein function. CONCLUSIONS: The p.X423Lfs mutation has previously been described in cases of atypical aniridia, but this is the first report demonstrating abnormal cone-driven ERG responses associated with this particular mutation of the PAX6 gene. ERG abnormalities have been documented in other mutations of the PAX6 gene, and we propose that the retinal pathology causing these ERG abnormalities may contribute to the photophobia experienced by patients with aniridia. Systematic ERG testing can aid in the diagnosis of PAX6-related disorders and may prove to be a useful tool to objectively assess responses to future treatments.
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Eletrorretinografia , Proteínas do Olho/genética , Mutação da Fase de Leitura , Proteínas de Homeodomínio/genética , Nistagmo Congênito/fisiopatologia , Fatores de Transcrição Box Pareados/genética , Fotofobia/fisiopatologia , Proteínas Repressoras/genética , Células Fotorreceptoras Retinianas Cones/fisiologia , Doenças Retinianas/fisiopatologia , Feminino , Heterozigoto , Humanos , Lactente , Masculino , Nistagmo Congênito/genética , Fator de Transcrição PAX6 , Linhagem , Estimulação Luminosa , Fotofobia/genética , Doenças Retinianas/genética , Adulto JovemRESUMO
Recognition of the gene implicated in a Mendelian disorder subsequently leads to an expansion of potential phenotypes associated with mutations in that gene as patients with features beyond the core phenotype are identified by sequencing. Here, we present a young girl with developmental delay, short stature despite a markedly advanced bone age, hypertrichosis without elbow hair, renal anomalies, and dysmorphic facial features, found to have a heterozygous, de novo, intragenic deletion encompassing exons 2-10 of the KMT2A (MLL) gene detected by whole exome sequencing. Heterozygous mutations in this gene were recently demonstrated to cause Wiedemann-Steiner syndrome (OMIM 605130). Importantly, retrospective analysis of this patient's chromosomal microarray revealed decreased copy number of two probes corresponding to exons 2 and 9 of the KMT2A gene, though this result was not reported by the testing laboratory in keeping with standard protocols for reportable size cutoffs for array comparative genomic hybridization. This patient expands the clinical phenotype associated with mutations in KMT2A to include variable patterns of hypertrichosis and a significantly advanced bone age with premature eruption of the secondary dentition despite her growth retardation. This patient also represents the first report of Wiedemann-Steiner syndrome due to an exonic deletion, supporting haploinsufficiency as a causative mechanism. Our patient also illustrates the need for sensitive guidelines for the reporting of chromosomal microarray findings that are below traditional reporting size cutoffs, but that impact exons or other genomic regions of known function.
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Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Doenças do Desenvolvimento Ósseo/genética , Éxons , Proteína de Leucina Linfoide-Mieloide/genética , Deleção de Sequência , Pré-Escolar , Hibridização Genômica Comparativa , Variações do Número de Cópias de DNA , Fácies , Feminino , Mãos/diagnóstico por imagem , Heterozigoto , Humanos , Fenótipo , Radiografia , SíndromeRESUMO
Whole exome sequencing made it possible to identify novel de novo mutations in genes that might be linked to human syndromes (genotype first analysis). We describe a female patient with a novel de novo SPOCK1 variant, which has not been previously been associated with a human phenotype. Her features include intellectual disability with dyspraxia, dysarthria, partial agenesis of corpus callosum, prenatal-onset microcephaly and atrial septal defect with aberrant subclavian artery. Previous genetic, cytogenomic and metabolic studies were unrevealing. At age 13 years, exome sequencing on the patient and her parents revealed a de novo novel missense mutation in SPOCK1 (coding for Testican-1) on chromosome 5q31: c.239A>T (p.D80V). This mutation affects a highly evolutionarily conserved area of the gene, replacing a polar aspartic acid with hydrophobic nonpolar valine, and changing the chemical properties of the protein product, likely representing a pathogenic variant. Previous microdeletions of 5q31 including SPOCK1 have suggested genes on 5q31 as candidates for intellectual disability. No mutations or variants in other genes potentially linked to her phenotype were identified. Testicans are proteoglycans belonging to the BM-40/SPARC/osteonectin family of extracellular calcium-binding proteins. Testican-1 is encoded by the SPOCK1 gene, and mouse models have been shown it to be strongly expressed in the brain and to be involved in neurogenesis. We hypothesize that because this gene function is critical for neurogenesis, mutations could potentially lead to a phenotype with developmental delay and microcephaly.
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Anormalidades Múltiplas/genética , Agenesia do Corpo Caloso/genética , Deficiências do Desenvolvimento/genética , Microcefalia/genética , Mutação de Sentido Incorreto , Proteoglicanas/genética , Adolescente , Análise Mutacional de DNA/métodos , Exoma/genética , Feminino , HumanosRESUMO
X-linked Alport syndrome is a form of progressive renal failure caused by pathogenic variants in the COL4A5 gene. More than 700 variants have been described and a further 400 are estimated to be known to individual laboratories but are unpublished. The major genetic testing laboratories for X-linked Alport syndrome worldwide have established a Web-based database for published and unpublished COL4A5 variants ( https://grenada.lumc.nl/LOVD2/COL4A/home.php?select_db=COL4A5 ). This conforms with the recommendations of the Human Variome Project: it uses the Leiden Open Variation Database (LOVD) format, describes variants according to the human reference sequence with standardized nomenclature, indicates likely pathogenicity and associated clinical features, and credits the submitting laboratory. The database includes non-pathogenic and recurrent variants, and is linked to another COL4A5 mutation database and relevant bioinformatics sites. Access is free. Increasing the number of COL4A5 variants in the public domain helps patients, diagnostic laboratories, clinicians, and researchers. The database improves the accuracy and efficiency of genetic testing because its variants are already categorized for pathogenicity. The description of further COL4A5 variants and clinical associations will improve our ability to predict phenotype and our understanding of collagen IV biochemistry. The database for X-linked Alport syndrome represents a model for databases in other inherited renal diseases.
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Colágeno Tipo IV/genética , Bases de Dados de Ácidos Nucleicos , Nefrite Hereditária/genética , Humanos , FenótipoRESUMO
PURPOSE: X-linked juvenile retinoschisis (XLRS) is a vitreoretinal dystrophy characterized by schisis (splitting) of the inner layers of the neuroretina. Mutations within the retinoschisis (RS1) gene are responsible for this disease. The mutation spectrum consists of amino acid substitutions, splice site variations, small indels, and larger genomic deletions. Clinically, genomic deletions are rarely reported. Here, we characterize two novel full exonic deletions: one encompassing exon 1 and the other spanning exons 4-5 of the RS1 gene. We also report the clinical findings in these patients with XLRS with two different exonic deletions. METHODS: Unrelated XLRS men and boys and their mothers (if available) were enrolled for molecular genetics evaluation. The patients also underwent ophthalmologic examination and in some cases electroretinogram (ERG) recording. All the exons and the flanking intronic regions of the RS1 gene were analyzed with direct sequencing. Two patients with exonic deletions were further evaluated with array comparative genomic hybridization to define the scope of the genomic aberrations. After the deleted genomic region was identified, primer walking followed by direct sequencing was used to determine the exact breakpoints. RESULTS: Two novel exonic deletions of the RS1 gene were identified: one including exon 1 and the other spanning exons 4 and 5. The exon 1 deletion extends from the 5' region of the RS1 gene (including the promoter) through intron 1 (c.(-35)-1723_c.51+2664del4472). The exon 4-5 deletion spans introns 3 to intron 5 (c.185-1020_c.522+1844del5764). CONCLUSIONS: Here we report two novel exonic deletions within the RS1 gene locus. We have also described the clinical presentations and hypothesized the genomic mechanisms underlying these schisis phenotypes.
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Éxons/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Retinosquise/genética , Deleção de Sequência/genética , Criança , Quebra Cromossômica , Proteínas do Olho/genética , Feminino , Fundo de Olho , Testes Genéticos , Humanos , Masculino , Tomografia de Coerência ÓpticaRESUMO
PURPOSE: Mendelian disorders are most commonly caused by mutations identifiable by DNA sequencing. Exonic deletions and duplications can go undetected by sequencing, and their frequency in most Mendelian disorders is unknown. METHODS: We designed an array comparative genomic hybridization (CGH) test with probes in exonic regions of 589 genes. Targeted testing was performed for 219 genes in 3,018 patients. We demonstrate for the first time the utility of exon-level array CGH in a large clinical cohort by testing for 136 autosomal dominant, 53 autosomal recessive, and 30 X-linked disorders. RESULTS: Overall, 98 deletions and two duplications were identified in 53 genes, corresponding to a detection rate of 3.3%. Approximately 40% of positive findings were deletions of only one or two exons. A high frequency of deletions was observed for several autosomal dominant disorders, with a detection rate of 2.9%. For autosomal recessive disorders, array CGH was usually performed after a single mutation was identified by sequencing. Among 138 individuals tested for recessive disorders, 10.1% had intragenic deletions. For X-linked disorders, 3.5% of 313 patients carried a deletion or duplication. CONCLUSION: Our results demonstrate that exon-level array CGH provides a robust option for intragenic copy number analysis and should routinely supplement sequence analysis for Mendelian disorders.
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Hibridização Genômica Comparativa/métodos , Éxons/genética , Doenças Genéticas Inatas/diagnóstico , Mutação/genética , Estudos de Coortes , Feminino , Deleção de Genes , Dosagem de Genes , Duplicação Gênica , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Humanos , Masculino , Análise da Randomização Mendeliana , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodosRESUMO
PURPOSE: To evaluate macular cone structure in patients with X-linked retinoschisis (XLRS) caused by mutations in exon 6 of the RS1 gene. METHODS: High-resolution macular images were obtained with adaptive optics scanning laser ophthalmoscopy (AOSLO) and spectral domain optical coherence tomography (SD-OCT) in two patients with XLRS and 27 age-similar healthy subjects. Retinal structure was correlated with best-corrected visual acuity, kinetic and static perimetry, fundus-guided microperimetry, full-field electroretinography (ERG), and multifocal ERG. The six coding exons and the flanking intronic regions of the RS1 gene were sequenced in each patient. RESULTS: Two unrelated males, ages 14 and 29, with visual acuity ranging from 20/32 to 20/63, had macular schisis with small relative central scotomas in each eye. The mixed scotopic ERG b-wave was reduced more than the a-wave. SD-OCT showed schisis cavities in the outer and inner nuclear and plexiform layers. Cone spacing was increased within the largest foveal schisis cavities but was normal elsewhere. In each patient, a mutation in exon 6 of the RS1 gene was identified and was predicted to change the amino acid sequence in the discoidin domain of the retinoschisin protein. CONCLUSIONS: AOSLO images of two patients with molecularly characterized XLRS revealed increased cone spacing and abnormal packing in the macula of each patient, but cone coverage and function were near normal outside the central foveal schisis cavities. Although cone density is reduced, the preservation of wave-guiding cones at the fovea and eccentric macular regions has prognostic and therapeutic implications for XLRS patients with foveal schisis. (Clinical Trials.gov number, NCT00254605.).
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Éxons/genética , Proteínas do Olho/genética , Mutação , Células Fotorreceptoras Retinianas Cones/patologia , Retinosquise/genética , Adolescente , Adulto , Contagem de Células , Eletrorretinografia , Fóvea Central , Humanos , Lasers , Masculino , Oftalmoscopia , Fenótipo , Reação em Cadeia da Polimerase , Retinosquise/fisiopatologia , Escotoma/diagnóstico , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Testes de Campo Visual , Campos Visuais/fisiologiaRESUMO
PURPOSE: Retinal dystrophy (RD) is a broad group of hereditary disorders with heterogeneous genotypes and phenotypes. Current available genetic testing for these diseases is complicated, time consuming, and expensive. This study was conducted to develop and apply a microarray-based, high-throughput resequencing system to detect sequence alterations in genes related to inherited RD. METHODS: A customized 300-kb resequencing chip, Retina-Array, was developed to detect sequence alterations of 267,550 bases of both sense and antisense sequence in 1470 exons spanning 93 genes involved in inherited RD. Retina-Array was evaluated in 19 patient samples with inherited RD provided by the eyeGENE repository and four Centre d'Etudes du Polymorphisme Humaine reference samples through a high-throughput experimental approach that included an automated PCR assay setup and quantification, efficient post-quantification data processing, optimized pooling and fragmentation, and standardized chip processing. RESULTS: The performance of the chips demonstrated that the average base pair call rate and accuracy were 93.56% and 99.86%, respectively. In total, 304 candidate variations were identified using a series of customized screening filters. Among 174 selected variations, 123 (70.7%) were further confirmed by dideoxy sequencing. Analysis of patient samples using Retina-Array resulted in the identification of 10 known mutations and 12 novel variations with high probability of deleterious effects. CONCLUSIONS: This study suggests that Retina-Array might be a valuable tool for the detection of disease-causing mutations and disease severity modifiers in a single experiment. Retinal-Array may provide a powerful and feasible approach through which to study genetic heterogeneity in retinal diseases.
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Proteínas do Olho/genética , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Retina/metabolismo , Distrofias Retinianas/genética , Éxons/genética , Testes Genéticos , Humanos , Mutação , Reação em Cadeia da PolimeraseRESUMO
PURPOSE: Bardet-Biedl syndrome (BBS) is genetically heterogeneous with 15 BBS genes currently identified, accounting for approximately 70% of cases. The aim of our study was to define further the spectrum of BBS mutations in a cohort of 44 European-derived American, 8 Tunisian, 1 Arabic, and 2 Pakistani families (55 families in total) with BBS. METHODS: A total of 142 exons of the first 12 BBS-causing genes were screened by dideoxy sequencing. Cases in which no mutations were found were then screened for BBS13, BBS14, BBS15, RPGRIP1L, CC2D2A, NPHP3, TMEM67, and INPP5E. RESULTS: Forty-three mutations, including 8 frameshift mutations, 10 nonsense mutations, 4 splice site mutations, 1 deletion, and 20 potentially or probably pathogenic missense variations, were identified in 46 of the 55 families studied (84%). Of these, 21 (2 frameshift mutations, 4 nonsense mutations, 4 splice site mutations, 1 deletion, and 10 missense variations) were novel. The molecular genetic findings raised the possibility of triallelic inheritance in 7 Caucasian families, 1 Arabian family, and 1 Tunisian patient. No mutations were detected for BBS4, BBS11, BBS13, BBS14, BBS15, RPGRIP1L, CC2D2A, NPHP3, TMEM67, or INPP5E. CONCLUSIONS: This mutational analysis extends the spectrum of known BBS mutations. Identification of 21 novel mutations highlights the genetic heterogeneity of this disorder. Differences in European and Tunisian patients, including the high frequency of the M390R mutation in Europeans, emphasize the population specificity of BBS mutations with potential diagnostic implications. The existence of some BBS cases without mutations in any currently identified BBS genes suggests further genetic heterogeneity.
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Síndrome de Bardet-Biedl/genética , Mutação , Proteínas/genética , Povo Asiático , Síndrome de Bardet-Biedl/diagnóstico , População Negra , Análise Mutacional de DNA , Etnicidade , Éxons/genética , Frequência do Gene , Humanos , Reação em Cadeia da Polimerase , População BrancaAssuntos
Descolamento Retiniano/diagnóstico , Neovascularização Retiniana/diagnóstico , Vasos Retinianos/patologia , Displasia Septo-Óptica/diagnóstico , Peso ao Nascer , Angiofluoresceinografia , Idade Gestacional , Humanos , Lactente , Fotocoagulação a Laser , Masculino , Descolamento Retiniano/cirurgia , Neovascularização Retiniana/cirurgia , Recurvamento da Esclera , VitrectomiaAssuntos
Anormalidades Múltiplas/patologia , Duplicação Cromossômica/genética , Cromossomos Humanos Par 11/genética , Proteínas do Olho/genética , Proteínas de Homeodomínio/genética , Fatores de Transcrição Box Pareados/genética , Fenótipo , Proteínas Repressoras/genética , Anormalidades Múltiplas/genética , Criança , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Anormalidades do Olho/genética , Anormalidades do Olho/patologia , Feminino , Humanos , Microcefalia/genética , Microcefalia/patologia , Hipotonia Muscular/genética , Hipotonia Muscular/patologia , Fator de Transcrição PAX6 , Convulsões/genética , Convulsões/patologiaRESUMO
PURPOSE: To explore the retinoschisin (RS1) protein biochemical phenotype from an RS1 exon-5 deletion/insertion frame-shift mutation in a family with X-linked retinoschisis (XLRS) and describe the clinical and electrophysiological features. METHODS: Six XLRS males underwent ophthalmic examination and electroretinogram (ERG) recording. The RS1 gene was sequenced. Mutant RS1-RNA and protein expression were assessed by transfecting COS-7 cells with minigene constructs. RESULTS: All six males carried the RS1 c354del1-ins18 mutation in which an 18-bp insertion replaced nucleotide 354, duplicating the adjacent upstream intron 4-to-exon 5 junction and creating a premature termination codon downstream. Analysis indicated normal pre-mRNA splicing producing mRNA transcripts. Truncated RS1 protein was expressed transiently but was degraded rapidly by a proteasomal pathway rather than by nonsense-mediated mRNA decay. Two boys, 1.5 and 5 years of age, had foveal cysts and minimal peripheral schisis, and retained near-normal scotopic b-wave amplitude and normal ERG waveforms. The 5-year-old's ERG was diminished when repeated 3 years later. Four older XLRS relatives 32 to 45 years old had substantial b-wave loss and strongly electronegative ERGs; three had overt macular atrophy. Cross-sectional family analysis showed the b-/a-wave amplitude ratio as inversely related to age in the six males. CONCLUSIONS: The c354del1-ins18 mutation caused an RS1-null biochemical phenotype and a progressive clinical phenotype in a 5-year-old boy, whereas the older XLRS relatives had macular atrophy and marked ERG changes. The phenotypic heterogeneity with age by cross-sectional study of this family mutation argues that XLRS disease is not stationary and raises questions regarding factors involved in progression.
Assuntos
Proteínas do Olho/genética , Mutação da Fase de Leitura , Mutação INDEL , Retina/fisiopatologia , Retinosquise/genética , Adulto , Animais , Atrofia , Células COS/metabolismo , Pré-Escolar , Chlorocebus aethiops , Estudos Transversais , Eletroforese em Gel de Poliacrilamida , Eletrorretinografia , Éxons/genética , Humanos , Lactente , Macula Lutea/patologia , Masculino , Pessoa de Meia-Idade , Mutagênese Sítio-Dirigida , Linhagem , Fenótipo , RNA Mensageiro/genética , Retinosquise/diagnóstico , Retinosquise/fisiopatologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tomografia de Coerência Óptica , Transfecção , Acuidade Visual/fisiologiaRESUMO
PURPOSE: To define the retinal pathology in a 91 year-old affected matriarch of a three-generation choroideremia family with multiple manifesting carriers. METHODS: Tissue from three different retinal areas was processed for immunohistochemistry. The macular area was processed for transmission electron microscopy. Cryosections were studied by indirect immunofluorescence, using well-characterized antibodies to cone cytoplasm, rhodopsin and cone opsins. The affected donor eyes were compared to a postmortem matched normal eye. RESULTS: The retina displayed areas of severe degeneration, with no photoreceptor outer segments, photoreceptor nuclear atrophy, and atrophy of the inner retina. Other retinal areas were near to normal. The RPE was severely degenerated, with thinning, pigment clumping and sub-epithelial debris deposition in all the areas examined. The choroid displayed depigmentation. Labeling with cone opsin antibodies revealed that cones were drastically affected: blue opsin was almost completely absent, while red/green opsins were distributed along the entire plasma membrane of the cell. Rhodopsin was also distributed along the entire rod plasma membrane. Ultrastructural analysis of the affected macula revealed the absence of RPE apical microvilli and basal infoldings. Instead, RPE's basal surface and choroid displayed the presence of banded fibers composed of clumps of wide-spacing collagen. Bruch's membrane was filled with vesicular structures, some smooth and others with bristle-like projections. CONCLUSIONS: The histological data suggests that the clinical manifestation in this donor is related to degenerative changes in the retina, RPE, and choroid.