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Lung involvement is not widely recognized as a complication of auto-inflammatory diseases. We present a broad approach to diagnose a severe form of autoinflammatory syndrome in an adult male patient. A 63-year-old Caucasian male presented with recurrent episodes of high fever, interstitial lung infiltration, and pleural effusion. Laboratory tests performed during the flares revealed lymphopenia and increased levels of C-reactive protein and ferritin. Broad diagnostic research on infections, connective tissue diseases, and malignancies yielded negative results. The patient's symptoms promptly resolved upon the administration of glucocorticoids; however, they reappeared when the prednisone dose was reduced. All attempts to administer immunomodulatory and immunosuppressive medications were ineffective. During follow-up, autoinflammatory syndrome was suspected; however, no pathological variants of monogenic autoinflammatory diseases were identified by genome-exome sequencing. The patient did not respond to interleukin 1 blockade with anakinra. He died due to multi-organ failure, and his condition remained unresolved until the first reported description of vacuole, E1 enzyme, X-linked, autoinflammatory, and somatic syndrome (VEXAS). We describe the diagnostic traps and reasoning process involved in establishing that the patient's symptoms were autoinflammatory in nature based on clinical symptoms, in addition to the proof of concept gained from genetic reevaluation and identification of pathogenic variants in the UBA1 gene. The aim of this review is to increase the awareness of VEXAS among pulmonologists. Genetic screening for UBA1 should be considered in patients with recurrent pneumonitis of unknown origin with elevated inflammatory markers and signs of cytopenia, especially if they require chronic steroids to control the disease. Respiratory manifestations are part of VEXAS; these may be dominant in the course of the disease and severe at presentation.
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Introduction: The X and Y chromosomes are responsible for the determination and differentiation of the gonads, and their numerical and structural abnormalities may cause the abnormal development of secondary sex characteristics. The presence of abnormalities concerning X chromosome can also contribute to many genetically heterogeneous diseases associated with cognitive impairment and intellectual disability. Purpose: This study shows the effect of aberrations of the maternal X chromosome on the abnormal development of the child. Patients and Methods: Ten women aged 26 to 40 years were consulted in genetic counselling clinic and subsequently subjected to cytogenetic and molecular tests due to abnormal psychomotor development of their children, in whom structural aberrations of the X chromosome had been detected. Results: Two women were diagnosed with changes in karyotype: 46,X,der(X)t(X;Y)(p22.3;q11.2) in one and 46,X,inv(X)(p21.2q13). Five women were diagnosed with microduplications in the short arm of the X chromosome; dupXp22.31 in one, and in four women dupXp22.33. The remaining three women were diagnosed with duplication in the long arm of the X chromosome; dupXq25 in one and dupXq26.3 in two women. Conclusion: Genetic analysis of the X chromosome, based on cytogenetic and molecular methods of the highest available resolution, is extremely important in women with reproductive failure. These methods allow establishing accurately the breakpoints and rearrangements in chromosomes, and assessment of the copy number variation (CNV) can explain phenotypic variability with apparently similar aberrations. A more precise characterization of the alterations is necessary for the correct genetic diagnosis, as well as determination of the carrier status and genetic risk in family members.
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Biotinidase deficiency (BD) is a rare autosomal recessive metabolic disease. Previously the disease was identified only by clinical signs and symptoms, and since recently, it has been included in newborn screening programs (NBS) worldwide, though not commonly. In Europe, BD prevalence varies highly among different countries, e.g., from 1:7 116 in Turkey to 1:75 842 in Switzerland. This paper aimed to present the molecular spectrum of BD (profound and partial forms) in Polish patients diagnosed within the national NBS of 1,071,463 newborns. The initial suspicion of BD was based on an abnormal biotinidase activity result determined in a dry blood spot (DBS) by colorimetric and by fluorimetric methods while biochemical verification was determined by serum biotinidase activity (as quantitative analysis). The final diagnosis of BD was established by serum enzyme activity and the BTD gene direct sequencing. The obtained results allowed for the estimation of disease prevalence (1:66,966 births, while 1:178,577 for profound and 1:107,146 for partial forms), and gave novel data on the molecular etiology of BD.
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Deficiencia de Biotinidasa , Biotinidasa/genética , Deficiencia de Biotinidasa/diagnóstico , Deficiencia de Biotinidasa/epidemiología , Deficiencia de Biotinidasa/genética , Humanos , Recién Nacido , Mutación , Tamizaje Neonatal/métodos , Polonia/epidemiología , PrevalenciaRESUMEN
BACKGROUND: Gitelman Syndrome (GS) is a hereditary tubulopathy associated with a biallelic inactivating mutations of the SLC12A3 gene encoding the thiazide-sensitive sodium-chloride cotransporter (NCCT). The typical clinical manifestation is a hypokalemic metabolic alkalosis with significant hypomagnesemia, and low urinary calcium excretion. Hypocalciuria is widely believed to be a hallmark of GS that distinguishes it from Barter's syndrome, presenting as hypercalciuria. The pathomechanism of hypocalciuria in GS is not fully elucidated. Up to date, a clinical course of GS with normocalciuria has been reported only in men, while women have a milder course of the disease with typical hypocalciuria, which is believed as the result of sex hormone. Additionally, there is a growing evidence that calcium channels of the distal nephron could be regulated by a variety of hormones, including aldosterone (Aldo). CASE PRESENTATION: We present the case of a 28-year-old Caucasian woman with asymptomatic, chronic hypokalemia, hypomagnesemia, hypochloremic alkalosis and normal urinary calcium excretion. A high renin levels with normal concentration of Aldo in serum have also been found. The values of blood pressure were low. Based on genetic studies, two heterozygous mutations in the trans position were confirmed: c.2186G>T (p.Gly729Val) and c.1247G>C (p.Cys416Ser) in the SLC12A3 gene, which ultimately confirmed the diagnosis of GS. CONCLUSIONS: We report here the first case of genetically confirmed GS manifested as normocalciuria in a Caucasian woman. Thus, our result does not confirm a role of sex hormones on the level of calciuria. Based on the results of normal Aldo concentration despite high renin level in our patient, we hypothesized that Aldo may be connecting with the level of urinary calcium excretion in patients with the GS.
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Alcalosis , Síndrome de Gitelman , Adulto , Alcalosis/genética , Calcio/metabolismo , Femenino , Síndrome de Gitelman/complicaciones , Síndrome de Gitelman/diagnóstico , Síndrome de Gitelman/genética , Humanos , Magnesio , Masculino , Mutación/genética , Renina/genética , Miembro 3 de la Familia de Transportadores de Soluto 12/genéticaRESUMEN
BACKGROUND: Several transferrin gene polymorphisms are known to result in a shifted IEF pattern. The aim of this study was to characterize the transferrin gene polymorphisms observed in patients from one referral center. MATERIALS AND METHODS: Patients with solely increased pentasialo-Tf were selected. The whole exome sequencing was done from probands (patients) and from DNA available from their parents. RESULTS: Two various polymorphisms in the transferrin gene: c.2012G>A, p.Gly671Glu and c.1027C>T, p.Arg343Trp, were found. CONCLUSIONS: Two transferrin gene polymorphisms: c.2012G>A, p.(Gly671Glu) and c.1027C>T, p.(Arg343Trp) solely correspond to an elevated pentasialo-Tf.
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Trastornos Congénitos de Glicosilación/diagnóstico , Trastornos Congénitos de Glicosilación/genética , Polimorfismo Genético , Transferrina/genética , Trastornos Congénitos de Glicosilación/sangre , Humanos , Focalización Isoeléctrica , Tamizaje Masivo/métodos , Secuenciación del Exoma/métodosRESUMEN
BACKGROUND: Autosomal recessive mutations in the AP-4 (adaptor protein complex 4) complex subunit ϵ - 1 (AP-4E1) gene on chromosome 15q21.2 are known to cause spastic paraplegia 51 (SPG51). The exact phenotype of SPG51 remains poorly characterized, because only a few families have been reported as carriers of the mutation. In addition, a previous study identified an autosomal dominant mutation in the AP4E1 gene as being associated with persistent stuttering. The aim of the current study was to characterize the phenotype of a paediatric patient with an identified novel AP4E1 mutation presenting with significant psychomotor retardation, intellectual disability and paraplegia. METHODS: Magnetic resonance imaging was used to identify hypoplasia of the corpus callosum. The DNA sample was tested using multiplex ligation-dependent probe amplification (MLPA) and array comparative genomic hybridization (aCGH). In addition, next-generation sequencing (NGS) was performed using the patient's DNA, and Sanger sequencing was performed using that of his family members. RESULTS: The phenotype was identified to be associated with a novel pathogenic variant c.942_943 + 3delinsCC in the AP4E1 gene. The patient manifested severely delayed psychomotor development, impaired global physical development and general illness. Movement disorders were evident during the neonatal period. CONCLUSIONS: The present study identifies a previously unknown disease-inducing AP4E1 gene mutation.
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ParaplejíaRESUMEN
Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) belongs to systemic autoinflammatory diseases (AIDs). Many of these syndromes are genetically conditioned and can be inherited. Diagnosis relies on clinical symptoms and should be confirmed by genetic testing. One of the most serious complications is AA amyloidosis. We present the diagnostic route of a 33-year-old male with AA amyloidosis and his children, leading to diagnosis of monogenic autoinflammatory syndrome, confirmed by genetic analysis. A novel variant of the in-frame insertion type in one allele of TNFRSF1A gene was found by whole exome sequencing and confirmed by Sanger sequencing, which allowed a diagnosis of TRAPS. Three-dimensional modeling was used to assess the structural changes introduced into TNFR1 molecule by the insertion. The analysis of the 3D model revealed that accommodation of the 4AA insert induces misalignment of three cysteine bridges (especially the C70-C96 bridge) in the extracellular domain, leading to putatively misfolded and improperly functioning TNFR1. Three of the patient's daughters inherited the same variant of the TNFRSF1A gene and presented TRAPS symptoms. TRAPS is a very rare disease, but in the presence of suggestive symptoms the genetic diagnostic workout should be undertaken. Early diagnosis followed by appropriate clinical management can prevent irreversible complications.
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Mutations in the X-linked androgen receptor (AR) gene cause complete androgen insensitivity syndrome (CAIS). CAIS may cause congenital sexual development disorder, which frequently develops into testicular tumors. Here, we describe a novel splice-site intron 1 mutation in AR leading to improper splicing and AR protein absence in CAIS gonads. We characterized a patient's postpubertal gonadal steroidogenic enzyme expression profile. Localization of both CYP11A1 and CYP17A1 enzymes was restricted to both Leydig tumor cells and adjacent to tumor gonadal tissues. Sertoli cells of the CAIS gonad showed abundant HSD17B3 protein, which is an adult Leydig cell marker that enables the conversion of androstenedione to testosterone. Such HSD17B3 expression is typical for fetal-type Sertoli cells in rodents. The postpubertal CAIS gonad of our patient was completely devoid of androgen signaling pathway activity. Plausibly, the postpubertal Leydig cells consisted of two distinct cell populations: postpubertal fetal-type Leydig cells that persisted as androgen-independent cells and immature adult Leydig cells that failed to differentiate. Taken together, in this CAIS postpubertal testis, both Leydig and fetal-type Sertoli cells participated in testosterone production. Our results indicate the importance of molecular analysis as well as the characterization of steroidogenic enzyme profiling in the CAIS patient's gonad.
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Síndrome de Resistencia Androgénica/genética , Receptores Androgénicos/genética , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Síndrome de Resistencia Androgénica/metabolismo , Andrógenos/metabolismo , Femenino , Feto/metabolismo , Gónadas/metabolismo , Hormonas/sangre , Humanos , Intrones , Masculino , Mutación , Receptores Androgénicos/metabolismoRESUMEN
SPG 8 is an autosomal dominant HSP, which phenotype results from KIAA0196 gene mutations. There have been twelve types of KIAA0196 mutations described in HGMD, which are located in conservative region of gene encoding strumpellin. We describe first patient in Poland, simultaneously second in the world with KIAA0196 mutation - p.V620A.
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Síndrome de Birt-Hogg-Dubé/complicaciones , Neumotórax/etiología , Adulto , Síndrome de Birt-Hogg-Dubé/genética , Síndrome de Birt-Hogg-Dubé/metabolismo , Análisis Mutacional de ADN , Femenino , Humanos , Persona de Mediana Edad , Mutación , Neumotórax/diagnóstico por imagen , Proteínas Proto-Oncogénicas/genética , Proteínas Supresoras de Tumor/genéticaRESUMEN
OBJECTIVES: The etiological factors of chronic pancreatitis (CP) in children differ from those in adults. To date, no study has assessed the clinical course of CP in young children. The aim of our study was to evaluate the etiology and the clinical presentation of the disease in children with disease onset before 5 years of age in comparison to later-onset of CP. METHODS: A total of 276 children with CP, hospitalized from 1988 to 2015, were enrolled in the study. Data on presentation, diagnostic findings, and treatment were reviewed. Two hundred sixty patients were screened for the most frequent mutations in major pancreatitis-associated genes, such as cationic trypsinogen/serine protease gene (PRSS1), serine protease inhibitor, Kazal type 1 gene (SPINK1), and cystic fibrosis transmembrane conductance regulator gene (CFTR). RESULTS: The disease onset before the age of 5 years occurred in 51 patients (group 1), the later onset in 225 patients (group 2). We found no significant discrepancies in distribution of the etiological factors between groups. The youngest patients (group 1) had more pancreatitis episodes (median 5.0 vs 3.00; Pâ<â0.05) and underwent surgeries more frequently (25.5% vs 8.9%; Pâ<â0.05). It could be associated with significantly longer follow-up in early onset group (median 6 vs 4 years; Pâ<â0.05). There were no differences in nutritional status or exocrine and endocrine pancreatic function. CONCLUSIONS: Early- and later-onset pancreatitis have similar etiological factors with predominance of gene mutations. The most frequent mutation found was p.Asn34Ser (N34S) in SPINK1 gene. The clinical presentation differed in number of pancreatitis episodes and frequency of surgeries.
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Edad de Inicio , Pancreatitis Crónica/fisiopatología , Adolescente , Niño , Preescolar , Femenino , Predisposición Genética a la Enfermedad , Humanos , Lactante , Estudios Longitudinales , Masculino , Mutación , Pancreatitis Crónica/etiología , Pancreatitis Crónica/genética , Factores de RiesgoRESUMEN
BACKGROUND: Available data from adult patients do not reflect natural course of hereditary pancreatitis (HP) in children. To date, no study has assessed the clinical course of HP in children. OBJECTIVE: To investigate the clinical course of HP in children and compare it to non-HP group with chronic pancreatitis (CP). METHODS: A group of 265 children with CP, hospitalized from 1988 to 2014, were enrolled in the study. Medical records of those patients were reviewed for data on presentation, diagnostic findings and treatment. All children were screened for mutations in major pancreatitis-associated genes, i.e. PRSS1, SPINK1, and CFTR. RESULTS: HP was diagnosed in 41 children (15.5%). Family history was positive in 88% of children with HP. Mutations of PRSS1 gene were found in 80% (33/41) of HP patients. We detected p.R122H, p.R122C, p.N29I, and p.E79K mutation in 34% (14/41), 27% (11/41), 12% (5/41), and 7% (3/41) of HP patients, respectively. Patients with paternal inheritance had first symptoms earlier than those with maternal inheritance (5.9 vs. 9.1 years; P < 0.05). Children with HP showed more severe changes in ERCP then those from non-HP group (2.05 Cambridge grade, vs. 1.6°; P < 0.05). ESWL was performed more frequently in HP group (12.2% vs. 3.1%; P < 0.05). There was no difference in age of disease onset (7.98 vs. 8.9 years; NS), pancreatic duct stenting (46.3% vs. 33%; NS), or number of surgical interventions (12.2% vs. 14.3%; NS) between both groups. CONCLUSIONS: Children with HP reveal significantly more severe clinical presentation of the disease than non-HP patients, despite the same age of onset.
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Pancreatitis/genética , Pancreatitis/patología , Adolescente , Edad de Inicio , Índice de Masa Corporal , Proteínas Portadoras/genética , Niño , Preescolar , Estudios de Cohortes , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Progresión de la Enfermedad , Exones , Femenino , Predisposición Genética a la Enfermedad , Humanos , Lactante , Masculino , Mutación/genética , Conductos Pancreáticos/patología , Pancreatitis Crónica/genética , Pancreatitis Crónica/patología , Polimorfismo de Longitud del Fragmento de Restricción , Estudios Retrospectivos , Tripsina/genética , Inhibidor de Tripsina Pancreática de Kazal , Adulto JovenRESUMEN
BACKGROUND: Clouston syndrome belongs to the family of ectodermal dysplasias. So far, a defective immune response has not been reported in Clouston syndrome. We report, for the first time, immunological particularities of a large multigenerational Polish family with Clouston syndrome. METHODS: Five members of the same family with Clouston syndrome, aged 6-76 years, and 20 healthy volunteers, aged 19-73 years, were enrolled in the study. In all participants, the ability of neutrophils to phagocytize opsonized Escherichia coli was assessed. Granulocyte oxidative burst was determined quantitatively, and an isolation of peripheral blood mononuclear cells and the detection of lymphocyte subsets were performed. All patients with Clouston syndrome underwent microscopic assessment of hair shafts, x-rays of the skull and hand bones, extra- and intraoral examination, and panoramic x-rays. RESULTS: Compared to the controls, all patients with Clouston syndrome presented with significantly reduced phagocytic activities of granulocytes and monocytes (P < 0.05). The percentages of granulocytes and monocytes being positive for oxidative burst were also significantly reduced in all patients with Clouston syndrome (P < 0.05). No disturbances in the percentages and absolute counts of T CD3+, T CD3+/CD4+, T CD3+/CD8+, natural killer, and B CD19+ cells were found. CONCLUSION: Although this study expands knowledge about Clouston syndrome, it also raises many questions. The results provide evidence of significantly reduced phagocytic activity and oxidative bursts of cells playing crucial roles in a nonspecific immune response. Further studies are required to understand the underlying mechanism of the hereby described abnormalities.
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Displasia Ectodérmica/inmunología , Monocitos/inmunología , Neutrófilos/inmunología , Linfocitos T , Adulto , Anciano , Linfocitos B , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Estudios de Casos y Controles , Niño , Conexina 30 , Conexinas/genética , Displasia Ectodérmica/genética , Granulocitos/inmunología , Humanos , Recuento de Linfocitos , Persona de Mediana Edad , Células T Asesinas Naturales , Fagocitosis , Estallido Respiratorio , Adulto JovenRESUMEN
Chronic pancreatitis is an inflammatory disorder of the pancreas. We analyzed CPA1, encoding carboxypeptidase A1, in subjects with nonalcoholic chronic pancreatitis (cases) and controls in a German discovery set and three replication sets. Functionally impaired variants were present in 29/944 (3.1%) German cases and 5/3,938 (0.1%) controls (odds ratio (OR) = 24.9, P = 1.5 × 10(-16)). The association was strongest in subjects aged ≤ 10 years (9.7%; OR = 84.0, P = 4.1 × 10(-24)). In the replication sets, defective CPA1 variants were present in 8/600 (1.3%) cases and 9/2,432 (0.4%) controls from Europe (P = 0.01), 5/230 (2.2%) cases and 0/264 controls from India (P = 0.02) and 5/247 (2.0%) cases and 0/341 controls from Japan (P = 0.013). The mechanism by which CPA1 variants confer increased pancreatitis risk may involve misfolding-induced endoplasmic reticulum stress rather than elevated trypsin activity, as is seen with other genetic risk factors for this disease.
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Carboxipeptidasas A/genética , Predisposición Genética a la Enfermedad , Pancreatitis Crónica/genética , Adolescente , Adulto , Edad de Inicio , Estudios de Casos y Controles , Niño , Humanos , Adulto JovenAsunto(s)
Enfermedades Pulmonares/diagnóstico , Enfermedades Pleurales/diagnóstico , Neumología/tendencias , Humanos , Enfermedades Pulmonares/epidemiología , Enfermedades Pulmonares/terapia , Publicaciones Periódicas como Asunto , Enfermedades Pleurales/epidemiología , Enfermedades Pleurales/terapia , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Investigación , Proyectos de Investigación , Tuberculosis PulmonarRESUMEN
Newborn screening for cystic fibrosis (NBS CF) in Poland was started in September 2006. Summary from 4 years' experience is presented in this study. The immunoreactive trypsin/DNA sequencing strategy was implemented. The group of 1,212,487 newborns were screened for cystic fibrosis during the programme. We identified a total of 221 CF cases during this period, including, 4 CF cases were reported to be omitted by NBS CF. Disease incidence in Poland based on the programme results was estimated as 1/4394 and carrier frequency as 1/33. The frequency of the F508del was similar (62%) to population data previously reported. This strategy allowed us to identify 29 affected infants with rare genotypes. The frequency of some mutations (eg, 2184insA, K710X) was assessed in Poland for the first time. Thus, sequencing assay seems to be accurate method for screening programme using blood spots in the Polish population.
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Fibrosis Quística/diagnóstico , Tamizaje Neonatal , Análisis de Secuencia de ADN , Fibrosis Quística/epidemiología , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Frecuencia de los Genes , Genotipo , Heterocigoto , Humanos , Incidencia , Recién Nacido , Mutación , Polonia/epidemiologíaRESUMEN
Recently, the potential risk of malignant cancer development in psoriatic patients has been highlighted. However, the relationship between the therapeutic schemes in psoriasis and possible neoplastic transformation has not been so far clearly explained. Phototherapy is considered a very effective therapeutic method in psoriasis, however, the pathogenesis of some malignancies may be associated with the exposure to UV radiation. p16 protein belongs to the defense mechanisms that protect cells from damage and mutagenic factors, such as UV radiation. In recent years, the altered expression of the p16 protein in the diseases not related to malignant transformation, including psoriasis, has been observed. These new observations suggest participation of the p16 protein in the mechanisms of psoriatic plaque formation.
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Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Melanoma/etiología , Terapia PUVA/efectos adversos , Psoriasis/complicaciones , Psoriasis/terapia , Neoplasias Cutáneas/etiología , Transformación Celular Neoplásica/patología , Humanos , Melanoma/patología , Psoriasis/metabolismo , Neoplasias Cutáneas/patologíaRESUMEN
BACKGROUND: Ichthyosis Follicularis, Atrichia and Photophobia (IFAP) syndrome is a rare genodermatosis due to mutations of the MBTPS2 gene. To date fewer than 40 cases have been described in the literature. OBJECTIVES: To present the first case of IFAP diagnosed in Poland due to a novel mutation of MBTPS2, and to review the relevant literature on this rare genodermatosis. MATERIALS & METHODS: A 16-year-old male presented with typical clinical features of IFAP, along with psoriasiform skin plaques, nail dystrophy, facial dysmorphy, mental retardation, severe skeletal abnormalities and chorea-like movements. DNA analysis was performed in the patient and his clinically unaffected mother, maternal grandmother and sisters. RESULTS: A novel missense mutation p.Cys334Tyr (c.1001G>A) was found in exon 8 of the MBTPS2 gene. This mutation was also found in his clinically unaffected mother and maternal grandmother, but not his healthy sisters. CONCLUSIONS: This patient with IFAP, the first described from Poland, is original by virtue of its extensive skeletal, cutaneous and neurologic manifestations and the novel missense mutation of the MBPTS2 gene. The identification of a novel mutation further expands the known MBPTS2 molecular repertoire and the spectrum of associated clinical findings.
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Alopecia/genética , Ictiosis/genética , Metaloendopeptidasas/genética , Mutación Missense , Fotofobia/genética , Adolescente , Alopecia/complicaciones , Humanos , Ictiosis/complicaciones , Masculino , Anomalías Musculoesqueléticas/genética , Fenotipo , Fotofobia/complicaciones , Polonia , Índice de Severidad de la Enfermedad , Enfermedades de la Piel/genéticaRESUMEN
Dystrophic Epidermolysis Bullosa (DEB) is a rare bullous genodermatosis caused by mutations in COL7A1, which encodes collagen type VII, the main component of anchoring fibrilis. DEB is inherited in an autosomal recessive and dominant manner, depending on the mutation type and localization. The aim of this study was to update the spectrum and frequency of COL7A1 mutations in a cohort of 42 Polish DEB patients. Using direct sequencing strategy we identified 25 different mutations, which gave us a detection rate of about 88%. In total, thirteen novel variants were identified, including three de novo mutations (p.G2680S, p.G2043R and p.Gly2064_Arg2069del). The panel of recessively inherited DEB causing recurrent mutations comprise of five variants: c.425A>G, c.682+1G>A, p.R2069C, p.W796X and, unreported before, c.7154delC, which accounts for about 59% of all mutated alleles in this group. In the dominant type of DEB, only p.G2043R was found to be recurrent and it was identified in 50% patients. Our results give further insight into the pathogenesis and epidemiology of DEB.