RESUMO
Biallelic pathogenic variants in the PNPLA6 gene cause a broad spectrum of disorders leading to gait disturbance, visual impairment, anterior hypopituitarism and hair anomalies. PNPLA6 encodes neuropathy target esterase (NTE), yet the role of NTE dysfunction on affected tissues in the large spectrum of associated disease remains unclear. We present a systematic evidence-based review of a novel cohort of 23 new patients along with 95 reported individuals with PNPLA6 variants that implicate missense variants as a driver of disease pathogenesis. Measuring esterase activity of 46 disease-associated and 20 common variants observed across PNPLA6-associated clinical diagnoses unambiguously reclassified 36 variants as pathogenic and 10 variants as likely pathogenic, establishing a robust functional assay for classifying PNPLA6 variants of unknown significance. Estimating the overall NTE activity of affected individuals revealed a striking inverse relationship between NTE activity and the presence of retinopathy and endocrinopathy. This phenomenon was recaptured in vivo in an allelic mouse series, where a similar NTE threshold for retinopathy exists. Thus, PNPLA6 disorders, previously considered allelic, are a continuous spectrum of pleiotropic phenotypes defined by an NTE genotype:activity:phenotype relationship. This relationship, and the generation of a preclinical animal model, pave the way for therapeutic trials, using NTE as a biomarker.
Assuntos
Fenótipo , Animais , Feminino , Humanos , Masculino , Camundongos , Aciltransferases , Hidrolases de Éster Carboxílico/genética , Mutação de Sentido Incorreto , Fosfolipases/genética , Doenças Retinianas/genéticaRESUMO
Retinitis pigmentosa (RP) is an inherited retinal dystrophy caused by the loss of photoreceptors and retinal pigment epithelial atrophy, leading to severe visual impairment or blindness. RP can be classified as nonsyndromic or syndromic with complex clinical phenotypes. Three unrelated Polish probands affected with retinitis pigmentosa coexisting with cerebellar ataxia were recruited for this study. Clinical heterogeneity and delayed appearance of typical disease symptoms significantly prolonged the patients' diagnostic process. Therefore, many clinical and genetic tests have been performed in the past. Here, we provide detailed clinical and genetic analysis results of the patients. Whole-exome sequencing (WES) and targeted NGS analysis allow the identification of four novel and two previously reported variants in the following genes: ABHD12, FLVCR1, and PNPLA6. The use of next-generation sequencing (NGS) methods finally allowed for confirmation of the clinical diagnosis. Ultra-rare diseases such as PHARC, PCARP, and Oliver-McFarlane syndromes were diagnosed in patients, respectively. Our findings confirmed the importance of the application of next-generation sequencing methods, especially in ultra-rare genetic disorders with overlapping features.
Assuntos
Sequenciamento do Exoma , Retinose Pigmentar , Humanos , Retinose Pigmentar/genética , Retinose Pigmentar/diagnóstico , Masculino , Feminino , Linhagem , Sequenciamento de Nucleotídeos em Larga Escala , Adulto , Ataxia Cerebelar/genética , Ataxia Cerebelar/diagnóstico , Proteínas de Membrana Transportadoras/genética , Monoacilglicerol Lipases/genética , Mutação , Ataxia/genética , Ataxia/diagnóstico , Fenótipo , Aciltransferases , Catarata , Fosfolipases , PolineuropatiasRESUMO
Ceroid lipofuscinosis type 3 (CLN3) is an autosomal recessive, neurodegenerative metabolic disease. Typical clinical symptoms include progressive visual loss, epilepsy of unknown etiology and dementia. Presence of lipofuscin deposits with typical pattern of 'fingerprints' and vacuolized lymphocytes suggest the diagnosis of CLN3. Cause of CLN3 are mutations in the CLN3 gene, among which the most frequently found is the large deletion 1.02 kb spreading on exons 7 and 8. We present 4 patients from 2 families, in whom the deterioration of visual quality and acuity was observed as first clinical sign, when they were a few years old and it was successively accompanied by symptoms of neurologic deterioration (like generalized convulsions with consciousness impairment). In all patients the 1.02 kb deletion in the CLN3 gene was detected in homo- or heterozygosity with other CLN3 pathogenic variant. Ultrastructural studies revealed abnormal structures corresponding to 'fingerprint' profiles (FPPs) in conjunctival endothelial cells. It should be emphasized that in patients with blindness of unknown cause the diagnosis of ceroid lipofuscinosis should be considered and in older children-especially CLN3. The facility of the analysis for the presence of 1.02 kb deletion and economic costs are a solid argument for intensive use of this test in the diagnostic procedure of CLN3.
Assuntos
Células Endoteliais , Lipofuscinoses Ceroides Neuronais , Criança , Humanos , Células Endoteliais/patologia , Chaperonas Moleculares/genética , Lipofuscinoses Ceroides Neuronais/genética , Lipofuscinoses Ceroides Neuronais/diagnóstico , Lipofuscinoses Ceroides Neuronais/patologia , Mutação , Éxons , Glicoproteínas de Membrana/genéticaRESUMO
Leber hereditary optic neuropathy (LHON) is a rare disorder causing a sudden painless loss of visual acuity in one or both eyes, affecting young males in their second to third decade of life. The molecular background of the LHON is up to 90%, genetically defined by a point mutation in mitochondrial DNA. Recently, an autosomal recessive form of LHON (LHONAR1, arLHON) has been discovered, caused by biallelic variants in the DNAJC30 gene. This study provides the results of the DNAJC30 gene analysis in a large group of 46 Polish patients diagnosed with LHON, together with the clinical characterization of the disease. The c.152A>G (p.Tyr51Cys) substitution in the DNAJC30 gene was detected in all the patients as homozygote or compound heterozygote. Moreover, we identified one novel variant, c.293A>G, p.(Tyr98Cys), as well as two ultra-rare DNAJC30 variants: c.293A>C, p.(Tyr98Ser), identified to date only in one individual affected with LHONAR1, and c.130_131delTC (p.Ser44ValfsTer8), previously described only in two patients with Leigh syndrome. The patients presented here represent the largest group of subjects with DNAJC30 gene mutations described to date. Based on our data, the autosomal recessive form of LHON caused by DNAJC30 gene mutations is more frequent than the mitochondrial form in Polish patients. The results of our study suggest that Sanger sequencing of the single-exon DNAJC30 gene should be a method of choice applied to identify a molecular background of clinically confirmed LHON in Polish patients. This approach will help to reduce the costs of molecular testing.
Assuntos
Proteínas de Choque Térmico HSP40 , Atrofia Óptica Hereditária de Leber , Humanos , Masculino , DNA Mitocondrial/genética , Mitocôndrias/genética , Mutação , Atrofia Óptica Hereditária de Leber/genética , Polônia , Doenças Raras/genética , Proteínas de Choque Térmico HSP40/genéticaRESUMO
Background: Cone-rod dystrophies (CRDs) are a heterogeneous group of inherited retinal diseases (IRDs) characterized by cone photoreceptor loss, that is followed by subsequent rod photoreceptor impairment. Case presentation: A 49-year-old man complaining of diminution of vision in both eyes (OU) was referred to our outpatient clinic. He reported visual loss for 5 years, but it was most progressive during the last few months. The best-corrected visual acuity (BCVA) at presentation was 0.4 in the right eye (RE) and 1.0 in the left eye (LE). Fundus fluorescein angiography (FFA) revealed granular hyperfluorescence in the macula and concomitant areas of capillary atrophy. Flash full-field electroretinography (ffERG) showed lowering of a and b waves as well as prolonged peak time in light-adapted conditions. However, outcomes of dark-adapted ERGs were within normal limits. Based on the constellation of clinical, angiographic, and electrophysiological tests findings, a diagnosis of IRD was suspected. Genetic testing showed a homozygous, pathogenic c.783G>A mutation in the cadherin-related family member 1 (CDHR1) gene, which confirmed CRD type 15 (CRD15). Conclusions: We demonstrate the clinical characteristics, retinal imaging outcomes, and genetic test results of a patient with CRD15. Our case contributes to expanding our knowledge of the clinical involvement of the pathogenic mutation c.783G>A in CDHR1 variants.
Assuntos
Distrofias de Cones e Bastonetes , Masculino , Humanos , Pessoa de Meia-Idade , Distrofias de Cones e Bastonetes/genética , Distrofias de Cones e Bastonetes/patologia , Tomografia de Coerência Óptica , Retina , Células Fotorreceptoras Retinianas Cones/patologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Mutação , Testes Genéticos , Proteínas Relacionadas a Caderinas , Proteínas do Tecido Nervoso/genéticaRESUMO
Aniridia is usually an autosomal dominant, rare disorder characterized by a variable degree of hypoplasia or the absence of iris tissue, with additional ocular abnormalities. Pathogenic variants in the PAX6 gene are associated with aniridia in most patients. However, in up to 30% of individuals, disease results from 11p13 chromosomal rearrangements. Here we present a patient with a clinical diagnosis of partial aniridia born to consanguineous Polish parents. The parents were asymptomatic and ophthalmologically normal. We performed PAX6 sequencing, array comparative genomic hybridization, quantitative real-time PCR, and whole genome sequencing. aCGH revealed a homozygous deletion of the DCDC1 gene fragment in the patient. The same, but heterozygous deletion, was detected in each of the patient's asymptomatic parents and brother. In the presented family, the signs and symptoms of aniridia are observed only in the homozygous proband. Whole genome sequencing analysis was performed to determine other possible causes of the disease and did not detect any additional or alternative potentially pathogenic variant. We report a novel homozygous deletion located in the 11p13 region, which does not include the PAX6 gene or any known PAX6 enhancers. To our best knowledge, this is the first reported case of a patient presented with isolated aniridia carrying a homozygous microdeletion downstream of the PAX6 gene.
Assuntos
Aniridia , Proteínas do Olho , Aniridia/diagnóstico , Aniridia/genética , Hibridização Genômica Comparativa , Proteínas do Olho/genética , Proteínas de Homeodomínio/genética , Homozigoto , Humanos , Masculino , Fator de Transcrição PAX6/genética , Linhagem , Deleção de SequênciaRESUMO
Anophthalmia and microphthalmia (A/M) represent severe developmental ocular malformations, corresponding, respectively, to absent eyeball or reduced size of the eye. Both anophthalmia and microphthalmia may occur in isolation or as part of a syndrome. Genetic heterogeneity has been demonstrated, and many genes have been reported to be associated with A/M. The advances in high-throughput sequencing have proven highly effective in defining the molecular basis of A/M. Nevertheless, there are still many patients with unsolved genetic background of the disease, who pose a significant challenge in the molecular diagnostics of A/M. Here we describe a family, with three males affected with the non-syndromic A/M. Whole exome-sequencing performed in Patient 1, revealed the presence of a novel probably pathogenic variant c.734A>G, (p.[Tyr245Cys]) in the PORCN gene. Pedigree analysis and segregation of the identified variant in the family confirmed the X-linked recessive pattern of inheritance. This is the first report of X-linked recessive non-syndromic A/M. Until now, pathogenic variants in the PORCN gene have been identified in the patients with Goltz syndrome, but they were inherited in X-linked dominant mode. The ocular phenotype is the only finding observed in the patients, which allows to exclude the diagnosis of Goltz syndrome.
Assuntos
Aciltransferases/genética , Anoftalmia/genética , Predisposição Genética para Doença , Proteínas de Membrana/genética , Microftalmia/genética , Adulto , Anoftalmia/complicações , Anoftalmia/patologia , Pré-Escolar , Exoma/genética , Feminino , Hipoplasia Dérmica Focal/genética , Hipoplasia Dérmica Focal/patologia , Genes Recessivos/genética , Genes Ligados ao Cromossomo X/genética , Heterogeneidade Genética , Humanos , Lactente , Masculino , Microftalmia/complicações , Microftalmia/patologia , Mutação/genética , Linhagem , Fenótipo , Sequenciamento do ExomaRESUMO
The ciliary chondrodysplasias represent a group of clinically and genetically heterogeneous disorders that affect skeleton development. Cilia are organelles that project from the surface of many cell types and play an important role during prenatal and postnatal human development. Cranioectodermal dysplasia (Sensenbrenner syndrome, CED) is a ciliopathy primarily characterized by craniofacial, skeletal, and ectodermal abnormalities. To date six genes have been associated with CED: IFT122, WDR35, WDR19, IFT140, IFT43, and IFT52. Prenatal diagnosis of CED is challenging, and genetic testing can facilitate making a correct diagnosis. Here, we report on a family with two male siblings affected by CED: a 3.5 year-old patient and his 2 year-old brother. Molecular analysis of the proband at 1 year of age revealed compound heterozygous variants in WDR35: c.3G>A [p.(Met1-Ala30delinsMetfsTer4)] and c.2522A>T [p.(Asp841Val)]. Ultrasound examination during the second pregnancy revealed an increased nuchal translucency of 4.5 mm and a hypoplastic nasal bone at 12 weeks of gestation. Prenatal diagnostic testing was offered because of an increased risk for chromosomal abnormalities and recurrence risk for CED. Prenatal genetic analysis of a chorionic villus sample detected the WDR35 variants previously identified in the elder brother. This is the first report of a prenatal genetic diagnosis in CED.
Assuntos
Osso e Ossos/anormalidades , Craniossinostoses/diagnóstico , Proteínas do Citoesqueleto/genética , Displasia Ectodérmica/diagnóstico , Peptídeos e Proteínas de Sinalização Intracelular/genética , Diagnóstico Pré-Natal , Osso e Ossos/patologia , Pré-Escolar , Craniossinostoses/genética , Craniossinostoses/patologia , Displasia Ectodérmica/genética , Displasia Ectodérmica/patologia , Feminino , Heterozigoto , Humanos , Lactente , Masculino , Polônia/epidemiologiaRESUMO
Leber hereditary optic neuropathy (LHON) is a mitochondrial disorder with symptoms limited to a single tissue, optic nerve, resulting in vision loss. In the majority of cases it is caused by one of three point mutations in mitochondrial DNA (mtDNA) but their presence is not sufficient for disease development, since ~50% of men and ~10% women who carry them are affected. Thus additional modifying factors must exist. In this study, we use next generation sequencing to investigate the role of whole mtDNA variation in male Polish patients with LHON and m.11778G > A, the most frequent LHON mutation. We present a possible association between mtDNA haplogroup K and variants in its background, a combination of m.3480A > G, m.9055G > A, m.11299 T > C and m.14167C > T, and LHON mutation. These variants may have a negative effect on m.11778G > A increasing its penetrance and the risk of LHON in the Polish population. Surprisingly, we did not observe associations previously reported for m.11778G > A and LHON in European populations, particularly for haplogroup J as a risk factor, implying that mtDNA variation is much more complex. Our results indicate possible contribution of novel combination of mtDNA genetic factors to the LHON phenotype.
Assuntos
DNA Mitocondrial/genética , Variação Genética/genética , Genoma Mitocondrial/genética , Mutação/genética , Atrofia Óptica Hereditária de Leber/epidemiologia , Atrofia Óptica Hereditária de Leber/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Óptica Hereditária de Leber/diagnóstico , Polônia/epidemiologia , Adulto JovemRESUMO
Achromatopsia is an autosomal recessive disorder characterized by cone photoreceptor dysfunction. We recently identified activating transcription factor 6 (ATF6) as a genetic cause of achromatopsia. ATF6 is a key regulator of the unfolded protein response. In response to endoplasmic reticulum (ER) stress, ATF6 migrates from the ER to Golgi to undergo regulated intramembrane proteolysis to release a cytosolic domain containing a basic leucine zipper (bZIP) transcriptional activator. The cleaved ATF6 fragment migrates to the nucleus to transcriptionally up-regulate protein-folding enzymes and chaperones. ATF6 mutations in patients with achromatopsia include missense, nonsense, splice site, and single-nucleotide deletion or duplication changes found across the entire gene. Here, we comprehensively tested the function of achromatopsia-associated ATF6 mutations and found that they group into three distinct molecular pathomechanisms: class 1 ATF6 mutants show impaired ER-to-Golgi trafficking and diminished regulated intramembrane proteolysis and transcriptional activity; class 2 ATF6 mutants bear the entire ATF6 cytosolic domain with fully intact transcriptional activity and constitutive induction of downstream target genes, even in the absence of ER stress; and class 3 ATF6 mutants have complete loss of transcriptional activity because of absent or defective bZIP domains. Primary fibroblasts from patients with class 1 or class 3 ATF6 mutations show increased cell death in response to ER stress. Our findings reveal that human ATF6 mutations interrupt distinct sequential steps of the ATF6 activation mechanism. We suggest that increased susceptibility to ER stress-induced damage during retinal development underlies the pathology of achromatopsia in patients with ATF6 mutations.
Assuntos
Fator 6 Ativador da Transcrição/metabolismo , Defeitos da Visão Cromática/genética , Defeitos da Visão Cromática/metabolismo , Mutação/genética , Morte Celular/genética , Linhagem Celular , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/genética , Fibroblastos/metabolismo , Complexo de Golgi/metabolismo , Células HEK293 , Humanos , Chaperonas Moleculares/metabolismo , Transcrição Gênica/genéticaRESUMO
Purpose: The aim of this study was to identify the molecular genetic basis of cone-rod dystrophy in 18 unrelated families of Polish origin. Cone-rod dystrophy is one of the inherited retinal dystrophies, which constitute a highly heterogeneous group of disorders characterized by progressive dysfunction of photoreceptors and retinal pigment epithelium (RPE) cells. Methods: The study group was composed of four groups of patients representing different Mendelian inheritance of the disease: autosomal dominant (AD), autosomal recessive (AR), X-linked recessive (XL), and autosomal recessive or X-linked recessive (AR/XL). The combined molecular strategy included Sanger sequencing of the RPGR-ORF15 gene (three families with XL and three families with the AR/XL mode of inheritance), mutation-specific microarray analysis of the ABCA4 gene (five families with the AR mode of inheritance and two families with the AR/XL mode of inheritance), targeted next-generation sequencing (NGS) of inherited retinal disease-associated (IRD) genes (seven families with the AD mode of inheritance and five families with the AR mode of inheritance), and whole exome sequencing, performed in select families who had been mutation-negative in the analysis with the targeted NGS panel (one family with the AD mode of inheritance, one family with the AR mode of inheritance, and two families with the AR/XL mode of inheritance). Results: Based on this combined strategy, we managed to identify potentially causative variants in seven out of 18 families with CRD. Five of these variants are novel: c.3142_3143dupAA, p.(Glu1049Argfs*41) in the RPGR-ORF15 gene, two variants: c.1612delT, p.(Trp538Glyfs*15) and c.2389dupG, p.(Ile798Hisfs*20) in the PROM1 gene in one family, c.592A>C, p.(Ser198Arg) in the PRPH2 gene and the variant c.1691A>G, p.(Asp564Gly) in the ATF6 gene that we have already reported to be pathogenic. NGS on the IRD panel allowed the molecular basis of CRD to be identified in four out of 14 families with a total detection rate of 38%. WES allowed identification of the molecular genetic basis of CRD in one family. Conclusions: This is the first report on the spectrum of disease genes and pathogenic variants causing CRD in the Polish population. The study presents five novel variants identified in four genes and therefore, broadens the spectrum of probable pathogenic variants associated with CRD.
Assuntos
Antígeno AC133/genética , Transportadores de Cassetes de Ligação de ATP/genética , Fator 6 Ativador da Transcrição/genética , Transtornos Cromossômicos/genética , Distrofias de Cones e Bastonetes/genética , Proteínas do Olho/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Periferinas/genética , Adolescente , Adulto , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/patologia , Estudos de Coortes , Distrofias de Cones e Bastonetes/diagnóstico , Distrofias de Cones e Bastonetes/patologia , Feminino , Expressão Gênica , Genes Dominantes , Genes Recessivos , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Polônia , Polimorfismo Genético , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Análise de Sequência de DNARESUMO
Jalili syndrome is a rare disorder inherited in an autosomal recessive pattern manifesting as a combination of cone-rod dystrophy including progressive loss of visual acuity, color blindness, photophobia, and amelogenesis imperfecta with hypoplastic, immature, or hypocalcified dental enamel. It is caused by mutations in CNNM4, which encodes the ancient conserved domain protein 4. Here we report three brothers with Jalili syndrome and muscle overgrowth of the legs. Myopathic changes were found in needle electromyography. Mutational analysis showed in all three brothers a novel likely pathogenic homozygous missense substitution in exon 1 (c.1076T>C, p.(Leu359Pro)) of CNNM4. Both parents were carriers for the variant. In order to exclude other causative variants that could modify the patients' phenotype we performed exome sequencing and MLPA analysis of the DMD gene in Patient 1. These analyses did not identify any additional variants. Our results expand the mutational spectrum associated with Jalili syndrome and suggest that mild myopathy with muscle overgrowth of the legs could be a newly identified manifestation of the disorder.
Assuntos
Amelogênese Imperfeita/genética , Proteínas de Transporte de Cátions/genética , Distrofias de Cones e Bastonetes/genética , Retinose Pigmentar/genética , Amelogênese Imperfeita/fisiopatologia , Distrofias de Cones e Bastonetes/fisiopatologia , Consanguinidade , Distrofina/genética , Eletromiografia , Éxons , Homozigoto , Humanos , Masculino , Mutação , Linhagem , Fenótipo , Retinose Pigmentar/fisiopatologia , Acuidade Visual/genéticaRESUMO
Variation in the ABCA4 locus has emerged as the most prevalent cause of monogenic retinal diseases. The study aimed to discover causative ABCA4 mutations in a large but not previously investigated cohort with ABCA4-related diseases originating from Central Europe and to refine the genetic relevance of all identified variants based on population evidence. Comprehensive clinical studies were performed to identify patients with Stargardt disease (STGD, n = 76) and cone-rod dystrophy (CRD, n = 16). Next-generation sequencing targeting ABCA4 was applied for a widespread screening of the gene. The results were analyzed in the context of exome data from a corresponding population (n = 594) and other large genomic databases. Our data disprove the pathogenic status of p.V552I and provide more evidence against a causal role of four further ABCA4 variants as drivers of the phenotype under a recessive paradigm. The study identifies 12 novel potentially pathogenic mutations (four of them recurrent) and a novel complex allele p.[(R152*; V2050L)]. In one third (31/92) of our cohort we detected the p.[(L541P; A1038V)] complex allele, which represents an unusually high level of genetic homogeneity for ABCA4-related diseases. Causative ABCA4 mutations account for 79% of STGD and 31% of CRD cases. A combination of p.[(L541P; A1038V)] and/or a truncating ABCA4 mutation always resulted in an early disease onset. Identification of ABCA4 retinopathies provides a specific molecular diagnosis and justifies a prompt introduction of simple precautions that may slow disease progression. The comprehensive, population-specific study expands our knowledge on the genetic landscape of retinal diseases.
Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , DNA/genética , Mutação , Distrofias Retinianas/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Adolescente , Alelos , Análise Mutacional de DNA , Europa (Continente)/epidemiologia , Feminino , Frequência do Gene , Variação Genética , Humanos , Masculino , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Prevalência , Distrofias Retinianas/epidemiologia , Distrofias Retinianas/metabolismo , Adulto JovemRESUMO
Background: Molecular analysis of the NDP gene to confirm and precise the clinical diagnosis in two patients with X-linked familial exudative vitreoretinopathy (XL-FEVR). Material and methods: We report two patients from unrelated families with NDP gene mutations: a 14-month-old boy (p1) who was found to have severe exudative vitreoretinopathy and a 4-year-old boy with exudative vitreoretinopathy (p2). An extensive clinical examination of the probands, including slit-lamp examination, B-mode ultrasonography and magnetic resonance imaging was conducted, along with genetic analysis of NDP gene. Results: Clinical findings in patient 1 included no light perception, total retinal detachment and hyperplastic primary vitreous in both eyes. The genetic analysis of the NDP gene enabled to identify the novel frameshift mutation c.222_c223insCG in p1 leading to the premature stop codon and production of aberrant norrin protein. In P2, clinical presentation included high myopia with astigmatism, unilateral fibrous bands and retinal detachment. Genetic testing revealed known point mutation c.362G>A leading to amino-acid alteration and improper protein. Conclusions: Mutation screening of NDP gene identified two different mutations in this region, one of which has not been previously reported.
Assuntos
Cegueira/congênito , Proteínas do Olho/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Proteínas do Tecido Nervoso/genética , Doenças do Sistema Nervoso/genética , Doenças Retinianas/genética , Espasmos Infantis/genética , Cegueira/genética , Pré-Escolar , Análise Mutacional de DNA , Oftalmopatias Hereditárias , Vitreorretinopatias Exsudativas Familiares , Genes Ligados ao Cromossomo X , Testes Genéticos , Humanos , Masculino , Degeneração RetinianaRESUMO
PURPOSE: To identify the genetic basis of achromatopsia (ACHM) in four patients from four unrelated Polish families. METHODS: In this study, we investigated probands with a clinical diagnosis of ACHM. Ophthalmologic examinations, including visual acuity testing, color vision testing, and full-field electroretinography (ERG), were performed in all patients (with the exception of patient p4, who had no ERG). Direct DNA sequencing encompassing the entire coding region of the CNGB3 gene, eight exons of the GNAT2 gene, and exons 5-7 of the CNGA3 gene was performed. Segregation analysis for the presence and independent inheritance of two mutant alleles was performed in the three families available for study. RESULTS: All patients showed typical achromatopsia signs and symptoms. Sequencing helped detect causative changes in the CNGB3 gene in all probands. Eight different mutations were detected in the CNGB3 gene, including five novel mutations: two splice site mutations (c.1579-1G>A and c.494-2A>T), one nonsense substitution (c.1194T>G), and two frame-shift mutations (c.393_394delGCinsTCCTGGTGA and c.1366delC). We also found three mutations: one splice site (c.1578+1G>A) and two frame-shift deletions that had been previously described (c.819_826del and c.1148delC). All respective parents were shown to be heterozygous carriers for the mutation detected in their children. CONCLUSIONS: The present study reports five novel mutations in the CNGB3 gene, and thus broadens the spectrum of probably pathogenic mutations associated with ACHM. Together with molecular data, we provide a brief clinical description of the affected individuals.
Assuntos
Defeitos da Visão Cromática/genética , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Mutação , Adulto , Sequência de Bases , Criança , Códon sem Sentido , Defeitos da Visão Cromática/fisiopatologia , Análise Mutacional de DNA , Eletrorretinografia , Feminino , Mutação da Fase de Leitura , Humanos , Masculino , Linhagem , Polônia , Sítios de Splice de RNA , Deleção de SequênciaRESUMO
Patients with intragenic mutations of the VHL gene have a typical disease presentation. However in cases of large VHL gene deletions which involve other genes in the proximity of the VHL gene a presentation of the disease can be different. To investigate whether large VHL deletions that remove the FANCD2 gene have an effect on the disease phenotype, we studied a family with a 50 kb large deletion encompassing these two genes. Four patients in this family were affected by VHL-related lesions. However one carrier of the deletion also had bilateral ductal breast cancer at age 46 and 49. Both tumors were of ~2 cm in diameter. On one side lymph nodes were affected. One tumor was ER- and PR-negative (HER2 s unknown) and the second was ER- and PR-positive, and HER2-negative. Our study suggests that a deletion of FANCD2 gene, an important gene in the DNA repair pathway, may be associated with an increased risk of breast cancer, but further studies are needed in this regard.
RESUMO
We report three patients with the novel variant c.100 + 1G > A of the TBCE gene and describe the presented clinical phenotype in detail. We also systematically reviewed the literature for clinical similarities and dissimilarities among all known patients with pathogenic TBCE variants. The clinical phenotype observed in patients with pathogenic TBCE variants is broader than previously described. Homozygous carriers of the c.100 + 1G > A variant exhibit a markedly milder clinical course, with no deviations in the calcium-phosphate metabolism and central nervous system pathology in MRI studies. Additionally, two patients manifest highly specific symptoms such as a rigid spine, eosinophilia, neutropenia, and nocturnal hypoxemia. Furthermore, cryptorchidism was observed in male patients. The identification of the pathogenic c.100 + 1G > A variant has thus far been limited to patients of Central-Eastern European descent, suggesting a potential founder mutation in this population.
RESUMO
Advances in gene therapy and genome editing give hope that new treatments will soon be available for inherited eye diseases that together affect a significant proportion of the adult population. New solutions are needed to make genetic diagnosis fast and affordable. This is the first study of such a large group of patients with inherited retinal dystrophies (IRD) and inherited optic neuropathies (ION) in the Polish population. It is based on four years of diagnostic analysis using a broad, targeted NGS approach. The results include the most common pathogenic variants, as well as 91 novel causative variants, including frameshifts in the cumbersome RPGR ORF15 region. The high frequency of the ABCA4 complex haplotype p.(Leu541Pro;Ala1038Val) was confirmed. Additionally, a deletion of exons 22-24 in USH2A, probably specific to the Polish population, was uncovered as the most frequent copy number variation. The diagnostic yield of the broad NGS panel reached 64.3% and is comparable to the results reported for genetic studies of IRD and ION performed for other populations with more extensive WES or WGS methods. A combined approach to identify genetic causes of all known diseases manifesting in the posterior eye segment appears to be the optimal choice given the currently available treatment options and advanced clinical trials.
RESUMO
Glioblastoma multiforme (GBM) is the most aggressive malignant brain tumour. The average survival time for a patient diagnosed with GBM, using standard treatment methods, is several months. Authors of the article pose a direct question: Is it possible to treat GBM solely with radioactive iodine (¹³¹I) therapy without employing the sodium iodide symporter (NIS) gene? After all, NIS has been detected not only in the thyroid but also in various tumours. The main author of this article (A.C.), with the assistance of her colleagues (physicians and pharmacologists), underwent ¹³¹I therapy after prior iodine inhibition, resulting in approximately 30% reduction in tumour size as revealed by magnetic resonance imaging (MRI). Classical therapy for GBM encompasses neurosurgery, conventional radiotherapy, and chemotherapy (e.g. temozolomide). Currently, tyrosine kinase inhibitors (imatinib, sunitinib, and sorafenib) are being used. Additionally, novel drugs such as crizotinib, entrectinib, or larotrectinib are being applied. Recently, personalised multimodal immunotherapy (IMI) based on anti-tumour vaccines derived from oncolytic viruses has been developed, concomitant with the advancement of cellular and molecular immunology. Thus, ¹³¹I therapy has been successfully employed for the first time in the case of GBM recurrence.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Radioisótopos do Iodo , Humanos , Glioblastoma/radioterapia , Glioblastoma/terapia , Glioblastoma/tratamento farmacológico , Radioisótopos do Iodo/uso terapêutico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/terapia , Recidiva Local de Neoplasia/prevenção & controle , Terapia CombinadaRESUMO
According to the latest guidelines of European and American medical societies, genetic testing (GT) is essential in cardiovascular diseases for establishing diagnosis, predicting prognosis, enabling initiation of disease-modifying therapy, and preventing sudden cardiac death. The GT result may be relevant for cascade GT in the patient's relatives, for planning his/her profession and physical activity, and for procreative counseling. This position statement has been prepared due to the scarcity of GT in cardiovascular diseases in Poland and the need to expand its availability. We give a concise description of the genetic background of cardiomyopathies, channelopathies, aortopathies, familial hypercholesterolemia, pheochromocytomas, and paragangliomas. The article discusses various aspects of GT in specific populations, such as children or athletes, and also presents prenatal genetic diagnostics. We propose recommendations for GT and counselling, which take into account Polish needs and capabilities. We give an outline of legal regulations, good clinical practice in GT with respect for patient rights, the role of cardiologists and clinical geneticists in GT planning and post-test counseling, and the requirements for laboratories performing genetic tests. The Polish Cardiac Society and Polish Society of Human Genetics experts speak with one voice with cardiovascular patient communities to underline the need for a law on GT and increasing the availability of GT for cardiovascular patients.