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Basal cell nevus syndrome (BCNS), or Gorlin syndrome, is a rare autosomal dominant disorder caused by mutations in the tumor suppressor gene PTCH1 with complete penetrance and variable expressivity characterized by a broad spectrum of developmental anomalies and a predisposition to neoplasms. Herein, we report a novel de novo splice site mutation in the PTCH1 gene related to mild developmental delay and autistic traits in a 4-year-old male patient.
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BACKGROUND: Myopathy with extrapyramidal signs (MPXPS) is an autosomal recessive mitochondrial disorder which is caused by mutation in mitochondrial calcium uptake 1 (MICU1) gene located on chromosome 10q22.1. Next Generation Sequencing (NGS) technology is the most effective method for identification of pathogenic variants with the ability to overcome some limitations which Sanger sequencing may encountered. There are few reports on this rare disease around the world and here in this study we first revealed genetic identification of two affected individuals in an Iranian family with a novel mutation. CASE PRESENTATION: The proband was a 5-year-old girl from consanguenous parents. She was first clinically suspicious of affected with limb-girdle muscular dystrophy (LGMD). Muscle biopsy studies and autozygosity mapping, using four short tandem repeat (STR) markers linked to 6 genes of the most prevalent forms of LGMD, ruled out calpainopathy, dysferlinopathy, and sarcoglycanopathis. DNA sample of the proband was sent for NGS. Whole exome sequencing (WES) revealed a novel mutation c.1295delA in exon 13 of MICU1 gene. This homozygous deletion creates a frameshift and a premature stop codon downstream of canonical EF4 calcium binding motif of MICU1. According to the American College of Medical Genetics and Genomics (ACMG) guidline for sequence interpretation, this variant was a pathogenic one. Sanger sequencing in all family members confirmed the results of the WES. CONCLUSIONS: This study was the first report of MPXPS in Iranian population which also revealed a novel mutation in the MICU1 gene.
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Proteínas de Unión al Calcio/genética , Proteínas de Transporte de Catión/genética , Repeticiones de Microsatélite/genética , Proteínas de Transporte de Membrana Mitocondrial/genética , Enfermedades Musculares/genética , Distrofia Muscular de Cinturas/genética , Preescolar , Exoma/genética , Exones/genética , Tractos Extrapiramidales/metabolismo , Tractos Extrapiramidales/patología , Femenino , Mutación del Sistema de Lectura/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Homocigoto , Humanos , Irán/epidemiología , Enfermedades Musculares/patología , Distrofia Muscular de Cinturas/patología , Linaje , Eliminación de Secuencia/genética , Secuenciación del ExomaRESUMEN
Cohen syndrome is a rare autosomal recessive disorder characterized by hypotonia, obesity, developmental delay, mental retardation, and facial, oral, ophthalmic, and limb deformities. Mutations in VPS13B have been found to be responsible for this disorder. In the current report, we have assessed three Iranian families with developmental delay and skeletal deformities. Whole exome sequencing of the affected probands led to identification of the underlying genetic cause in these families. Three mutations were found in VPS13B gene. The detected mutations were c.4608_4609del (p.E1537Rfs*7), c.11486dupG (p.L3830Tfs*13), and c.10360dupC (p.L3454fs*7). The current study broadens the mutation spectrum of VPS13B gene and demonstrates different phenotypic features from classic Cohen syndrome. Moreover, the provided data can be used in genetic counseling and prenatal diagnosis of Iranian patients.
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Dedos/anomalías , Discapacidad Intelectual/genética , Microcefalia/genética , Hipotonía Muscular/genética , Mutación , Miopía/genética , Obesidad/genética , Fenotipo , Degeneración Retiniana/genética , Proteínas de Transporte Vesicular/genética , Adolescente , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/patología , Exoma , Dedos/patología , Humanos , Lactante , Discapacidad Intelectual/patología , Masculino , Microcefalia/patología , Hipotonía Muscular/patología , Miopía/patología , Obesidad/patología , Linaje , Degeneración Retiniana/patologíaRESUMEN
[This corrects the article DOI: 10.3892/br.2018.1095.].
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Niemann-Pick disease type C (NP-C) is a neurovisceral lipid storage disorder. At the cellular level, the disorder is characterized by accumulation of unesterified cholesterol and glycolipids in the lysosomal/late endosomal system. NP-C is transmitted in an autosomal recessive manner and is caused by mutations in either the NPC1 (95% of families) or NPC2 gene. The estimated disease incidence is 1 in 120,000 live births, but this likely represents an underestimate, as the disease may be under-diagnosed due to its highly heterogeneous presentation. Variants of adenosine triphosphatase (ATPase) subunit 6 and ATPase subunit 8 (ATPase6/8) in mitochondrial DNA (mtDNA) have been reported in different types of genetic diseases including NP-C. In the present study, the blood samples of 22 Iranian patients with NP-C and 150 healthy subjects as a control group were analyzed. The DNA of the blood samples was extracted by the salting out method and analyzed for ATPase6/8 mutations using polymerase chain reaction sequencing. Sequence variations in mitochondrial genome samples were determined via the Mitomap database. Analysis of sequencing data confirmed the existence of 11 different single nucleotide polymorphisms (SNPs) in patients with NP-C1. One of the most prevalent polymorphisms was the A8860G variant, which was observed in both affected and non-affected groups and determined to have no significant association with NP-C incidence. Amongst the 11 polymorphisms, only one was identified in the ATPase8 gene, while 9 including A8860G were observed in the ATPase6 gene. Furthermore, two SNPs, G8292A and C8792A, located in the non-coding region of mtDNA and the ATPase6 gene, respectively, exhibited significantly higher prevalence rates in NP-C1 patients compared with the control group (P<0.01). The present study suggests that there may be an association between mitochondrial ATPase6/8 mutations and the incidence of NP-C disease. In addition, the mitochondrial SNPs identified maybe pathogenic mutations involved in the development and prevalence of NP-C. Furthermore, these results suggest a higher occurrence of mutations in ATPase6 than in ATPase8 in NP-C patients.
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OBJECTIVE: Anticonvulsant drugs can cause various forms of skin drug reactions, ranging from exanthema to severe blistering reactions. An association between HLA-B*1502 allele and severe skin reactions have been reported. MATERIALS & METHODS: Fifteen patients with severe skin reactions following treatment with anticonvulsant drugs (Carbamazepine, lamotrigine, phenobarbital, primidone) and 15 controls (age-matched epileptic patients taking similar anticonvulsants without drug eruption) were included. They were referred to Mofid Children's Hospital in Tehran, Iran, between Jan 2012 to Jan 2014. Genomic DNA was extracted from peripheral blood of all patients and HLA- B*1502 genotype was detected by real-time PCR. RESULTS: None of the patients was positive for HLA- B*1502, but two patients in control group had positive HLA- B*1502. CONCLUSION: The HLA- B*1502 is not correlated with severe anticonvulsant drugs -induced skin reactions in Iranian children.
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Sarcoglycanopathies (SGCs) which are caused by mutations in SGCA, SGCB, SGCG or SGCD genes are a subgroup of autosomal-recessive limb-girdle-muscular-dystrophies (LGMD2). Although frequencies of mutations in these genes are different among populations, mutations in SGCA and SGCD, respectively, have the highest and lowest frequencies in most populations. Here, we report the proportion of mutations in SGC genes among a group of Iranian SGCs patients. Clinical features and results of SGC genes screening of 25 SGCs probands are presented. Large deletion mutations are confirmed with MLPA assays. In total, 15 candidate disease causing mutations were observed in the SGCA, SGCB, SGCG and SGCD genes; ten were novel. Fourteen (56%), seven (28%), three (12%) and one (4%) patient, respectively, carried mutations in SGCB, SGCG, SGCD and SGCA. The findings suggest that LGMD2E is the most common form of SGCs in the Iranian population and that LGMD2D is the rarest. Twelve LGMD2E cases carried the same mutation. To the best of knowledge, the mutation spectrum in SGCs is being reported for the first time in Iranian population. The finding will be beneficial for screening and genetic-counseling of SGCs patients in Iran.
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Mutación/genética , Sarcoglicanopatías/epidemiología , Sarcoglicanopatías/genética , Adolescente , Adulto , Niño , Salud de la Familia , Femenino , Técnicas Genéticas , Haplotipos , Humanos , Irán/epidemiología , Masculino , Estudios Retrospectivos , Adulto JovenRESUMEN
Sarcoglycanopathies (SGPs) constitute a subgroup of autosomal recessive limb girdle muscular dystrophies (LGMDs) which are caused by mutations in sarcoglycan (SGs) genes. SG proteins form a core complex consisting of α, ß, γ and δ sarcoglycans which are encoded by SGCA, SGCB, SGCG and SGCD genes, respectively. Genetic defect, in any of these SG proteins, results in instability of the whole complex. This effect can be helpful in interpreting muscle biopsy results. Autozygosity mapping is a gene mapping approach which can be applied in large consanguineous families for tracking the defective gene in most autosomal recessive disorders. In the present study, we used autozygosity mapping, to find the gene responsible for muscular dystrophy. Proband was a 10-year-old boy referred to our center for ruling out DMD (Duchenne muscular dystrophy). According to the pedigree and clinical reports, we assessed him for SGPs. Haplotyping, using the four short tandem repeat (STR) markers for each of the SG genes, showed that the phenotype may segregate with SGCB gene; and observing two crossing overs which occurred within the gene suggested that the mutation might be in the first two exons of SGCB gene. Mutation analysis showed a 26 bp duplication (10 bp before the initiation codon till 13 bp after the ATG start codon). This will cause a frameshift in protein synthesis.
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Mapeo Cromosómico/métodos , Distrofia Muscular de Cinturas/genética , Sarcoglicanos/genética , Adulto , Niño , Análisis Mutacional de ADN , Femenino , Humanos , Irán , Masculino , LinajeRESUMEN
OBJECTIVE AND IMPORTANCE: The sarcoglycanopathies (SGPs) are a subgroup of autosomal recessive limb girdle muscular dystrophies. They are caused by mutations in gamma, alpha, beta, and delta sarcoglycans (SGs) genes. Alpha-SGPs are the most frequent form of SGPs. Muscle biopsy studies in patients with SGPs have indicated that loss of one SG subunit leads to instability of whole SG complex. Autozygosity mapping is a powerful gene mapping approach for rare recessive inherited disorders in consanguineous families. CLINICAL PRESENTATION: In the present study, proband was a 9 year old girl from consanguineous parents. She was diagnosed at the age of 5 when she had problems climbing stairs. Her creatine kinase level was 16428 U/L. Proximal weakness and ankle contracture were also observed in the patient. TECHNIQUES: Autozygosity mapping, using short tandem repeat (STR) markers linked to the SG genes, showed co-segregation of the phenotype with STR markers linked to the SGCA (Alpha-sarcoglycan) gene. Her muscle biopsy also suggested alpha sarcoglycanopathy. Mutation analyses revealed a novel homozygous deletion of 11 base pairs in exon 4 of this gene. This deletion introduces a premature termination codon after the 4th amino acid. This will eliminate the expression of the downstream part of the extracellular domain of the protein. This domain has a critical role by associating with other molecules of dystrophin-glycoprotein complexes. CONCLUSION: IHC (Immunohistochemistry) studies combined with autozygosity mapping and mutation screening is an efficient diagnostic method in the SGPs.
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Mutación/genética , Sarcoglicanopatías/genética , Sarcoglicanos/genética , Niño , Consanguinidad , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Humanos , IránRESUMEN
DRESS syndrome (Drug Rash with Eosinophilia and Systemic Symptoms) is a potentially life-threatening syndrome, which reflects a serious hypersensitivity reaction to drugs, presenting by generalized skin rash, fever, eosinophilia, atypical lymphocytosis, and internal organ involvement. Herein a 21-month old male infant with DRESS and Encephalopathy syndrome is presented who complicated after phenobarbital usage that persisted due to phenytoin cream usage. The case received phenobarbital after a seizure disorder presented as "status epilepticus". He developed drug eruption, fever, hepatosplenomegaly, increased liver enzymes, encephalopathy and progressive loss of consciousness with extensive hyperintense white matter lesions in brain MRI. After discontinuation of phenobarbital and phenytoin, all symptoms were resolved, while brain MRI became normal after two months. To our best knowledge, this is the first reported case that developed leukoencephalopathy along with DRESS syndrome.
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Anticonvulsivantes/efectos adversos , Síndrome de Hipersensibilidad a Medicamentos/diagnóstico , Leucoencefalopatías/etiología , Fenobarbital/efectos adversos , Fenitoína/efectos adversos , Humanos , Lactante , MasculinoRESUMEN
OBJECTIVE: To elucidate the effects of antiepileptic drugs (AEDs) on bone health status of ambulatory epileptic children. METHODS: A total of 120 epileptic children aged 2-15 y were enrolled in three groups. The first group was on therapy with carbamazepine, phenobarbital or primidone. The second was treated with valproic acid and the third group was untreated. Serum calcium, phosphorous, total alkaline phosphatase, and parathyroid hormone levels were compared between groups. Bone mineral density tests were also performed at four sites of the lumbar spine and three sites of femoral neck and results were compared between the groups. RESULTS: Of all enrolled subjects, 67 patients (55.8 %) were vitamin D deficient. The three groups were not significantly different in terms of vitamin D, calcium, phosphorus, total alkaline phosphatase, and parathyroid hormone levels. While patients in first group had lower Z-score of femoral neck and lumbar spine compared to those on valproic acid, these values were also significantly different than that of the third group. CONCLUSIONS: It can be concluded that both enzyme-inducing AEDs and non enzyme-inducing AEDs decrease bone mineral density (BMD). Also alkaline phosphatase (ALP) is affected in ambulatory epileptic children on enzyme-inducing AEDs. Nevertheless, valproic acid (a non-enzyme-inducing agent) does not have the mentioned side effects.
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Anticonvulsivantes , Densidad Ósea/efectos de los fármacos , Epilepsia/tratamiento farmacológico , Deficiencia de Vitamina D , Absorciometría de Fotón/métodos , Adolescente , Fosfatasa Alcalina/sangre , Anticonvulsivantes/efectos adversos , Anticonvulsivantes/farmacología , Calcio/sangre , Niño , Preescolar , Epilepsia/sangre , Epilepsia/diagnóstico , Epilepsia/epidemiología , Femenino , Humanos , Irán/epidemiología , Efectos Adversos a Largo Plazo/inducido químicamente , Efectos Adversos a Largo Plazo/diagnóstico , Efectos Adversos a Largo Plazo/epidemiología , Masculino , Pacientes Ambulatorios , Hormona Paratiroidea/sangre , Estudios Retrospectivos , Estadística como Asunto , Deficiencia de Vitamina D/diagnóstico , Deficiencia de Vitamina D/epidemiología , Deficiencia de Vitamina D/etiologíaRESUMEN
Megalencephalic leukoencephalopathy with subcortical cysts (MLC) (MIM #604004) is a rare autosomal recessive neurological disorder characterized by macrocephaly, motor and cognitive decline, ataxia, spasticity and occasional seizures. Magnetic resonance imaging (MRI) shows diffusely abnormal and swollen white matter of the cerebral hemispheres and subcortical cysts in the anterior temporal and frontoparietal region. Mutations in MLC1(22q13.33) and GLIALCAM have been identified in patients with MLC. Mutations in MLC1 account for approximately 75% of the cases. MLC was suspected in eighteen Iranian patients from sixteen families based on positive clinical findings including macrocephaly beginning in the first year, neurocognitive deterioration, seizure or loss of consciousness after minor head trauma. All except two were born to consanguineous parents. Brain MRI images were compatible with MLC and confirmed the diagnosis. Sequencing of entire coding region of MLC1 was performed for seventeen patients and mutations in MLC1 were detected in all of them. Eight novel mutations and seven previously reported mutations were identified. This report shows that MLC is relatively common in Iranian population, as expected for rare diseases with high inbreeding, with a surprisingly high frequency of novel mutations.
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Quistes/genética , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/genética , Proteínas de la Membrana/genética , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Irán , Masculino , Datos de Secuencia Molecular , Mutación , Adulto JovenRESUMEN
OBJECTIVE: GM2-Gangliosidosis disease is a rare autosomal recessive genetic disorder that includes two disorders (Tay-Sachs and Sandhoff disease).These disorders cause a progressive deterioration of nerve cells and inherited deficiency in creating hexosaminidases A, B, and AB. MATERIALS & METHODS: Patients who were diagnosed withGM2-Gangliosidosis in the Neurology Department of Mofid Children's Hospital in Tehran, Iran from October 2009 to February 2014were included in our study. The disorder was confirmed by neurometabolic and enzyme level detection of hexosaminidases A, B, and AB in reference to Wagnester Laboratory in Germany. We assessed age, gender, past medical history, developmental status, clinical manifestations, and neuroimaging findings of 9 patients with Sandhoff disease and 9 with Tay Sachs disease. RESULTS: 83% of our patients were the offspring of consanguineous marriages. All of them had a developmental disorder as a chief complaint. 38%of patients had a history of developmental delay or regression and 22% had seizures. The patients with Sandhoff and Tay Sachs disease were followed for approximately 5 years and the follow-up showed all patients were bedridden or had expired due to refractory seizures, pneumonia aspiration, or swallowing disorders. Neuro-imaging findings included bilateral thalamic involvement, brain atrophy, and hypo myelination in near half of our patients (48%). CONCLUSION: According to the results of this study, we suggest that cherry-red spots, hyperacusis, refractory seizures, and relative parents in children with developmental delay and/or regression should be considered for assessment of GM2-Gangliosidosis disease.
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This report describes a case of megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome in a 1-year-old boy, born to healthy nonconsanguineous parents. Megalencephaly and bilateral postaxial polydactyly of upper and lower limbs were noted at birth. He had profound developmental delay and moderate hypotonia. Magnetic resonance imaging (MRI) of the brain revealed hydrocephalus, polymicrogyria in both frontal lobes and perisylvian regions, and thin corpus callosum. Array-comparative genomic hybridization was normal. The patient's clinical and radiologic findings fit the classic description of megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome. The possible overlap between megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome and other similar conditions is discussed.
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Anomalías Múltiples/diagnóstico , Hidrocefalia/diagnóstico , Malformaciones del Desarrollo Cortical/diagnóstico , Megalencefalia/diagnóstico , Polidactilia/diagnóstico , Encéfalo/patología , Ventrículos Cerebrales/patología , Discapacidades del Desarrollo/diagnóstico , Dominancia Cerebral/fisiología , Lóbulo Frontal/patología , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Hipotonía Muscular/diagnóstico , Síndrome , Lóbulo Temporal/patologíaRESUMEN
BACKGROUND: Neurodegeneration with brain iron accumulation (NBIA) constitutes a group of neurodegenerative disorders with pronounced iron deposition in the basal ganglia. PANK2 mutations are the most common cause of these disorders. C19orf12 was recently reported as another causative gene. We present phenotypic data and results of screening of PANK2 and C19orf12 in 11 unrelated Iranian NBIA patients. METHODS: Phenotypic data were obtained by neurologic examination, magnetic resonance imaging, and interviews. Mutation screening of PANK2 and C19orf12 was performed by sequencing. RESULTS: PANK2 and C19orf12 mutations were found in 7 and 4 patients, respectively. Phenotypic comparisons suggest that C19orf12 mutations as compared with PANK2 mutations result in a milder disease course. CONCLUSIONS: Mutations in both PANK2 and C19orf12 contributed significantly to NBIA in the Iranian patients. To the best of our knowledge, this is the first genetic analysis reported on a cohort of NBIA patients from the Middle East.
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Química Encefálica/genética , Trastornos Heredodegenerativos del Sistema Nervioso/genética , Trastornos Heredodegenerativos del Sistema Nervioso/metabolismo , Hierro/metabolismo , Proteínas Mitocondriales/genética , Mutación/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Adolescente , Adulto , Edad de Inicio , Estudios de Cohortes , Exones , Femenino , Humanos , Irán/epidemiología , Masculino , Medio Oriente/epidemiología , Mutación/fisiología , Reacción en Cadena de la Polimerasa , Adulto JovenRESUMEN
OBJECTIVE: Muscle biopsy is a very important diagnostic test in the investigation of a child with suspected neuromuscular disorder. The goal of this study was to review and evaluate pediatric muscle biopsies during a 2-year period with focus on histopathology diagnosis and correlations with other paraclinic studies. MATERIALS & METHODS: We investigated 100 muscle biopsies belonging to patients with clinical impression of neuromuscular disorder. These patients have been visited consecutively by pediatric neurologists during 2010 to 2012. Samples were investigated by standard enzyme histochemical and immunohistochemical techniques. RESULT: Sixty-nine (69%) males and 39 (39%) females with a mean age of 5.7 years were evaluated. Major pathologic diagnoses were Muscular dystrophy (48 cases), Neurogenic atrophy (18 cases), nonspecific myopathic atrophy (12cases), congenital myopathy (6 cases), storage myopathies (4 cases) and in 6 cases there was no specific histochemical pathologic finding. EMG was abnormal in 79 cases. Degree of correlation between EMG and biopsy result was significant in children ≥ 2 years of age. CONCLUSION: This study confirms the high diagnostic yields of muscle biopsy especially only if standard and new techniques such as enzyme study and immunohistochemistry are implemented. Also, we report 11 cases of Merosin negative congenital muscular dystrophy. This is the largest documented case series of Merosin deficient congenital muscular dystrophy reported from Iran.
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OBJECTIVE: Methylmalonic acidemia is one of the inborn errors of metabolism resulting in the accumulation of acylcarnitine in blood and increased urinary methylmalonic acid excretion. This disorder can have symptoms, such as neurological and gastrointestinal manifestations, lethargy, and anorexia. MATERIALS & METHODS: The patients who were diagnosed as methylmalonic acidemia in the Neurology Department of Mofid Children's Hospital in Tehran, Iran, between 2002 and 2012 were included in our study. The disorder was confirmed by clinical findings, neuroimaging findings, and neurometabolic and genetic assessment in reference laboratory in Germany. We assessed the age, gender, past medical history, developmental status, clinical manifestations, and neuroimaging findings of 20 patients with methylmalonic acidemia. RESULTS: Eighty percent of the patients were offspring of consanguineous marriages. Half of the patients had Failure to thrive (FTT) due to anorexia; 85% had history of developmental delay or regression, and 20% had refractory seizure, which all of them were controlled. The patients with methylmalonic acidemia were followed for approximately 5 years and the follow-up showed that the patients with early diagnosis had a more favorable clinical response in growth index, refractory seizure, anorexia, and neurodevelopmental delay. Neuroimaging findings included brain atrophy, basal ganglia involvement (often in putamen), and periventricular leukomalacia. CONCLUSION: According to the results of this study, we suggest that early assessment and diagnosis have an important role in the prevention of disease progression and clinical signs.
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OBJECTIVE: This research was designed to identify the validity and reliability of the Prescreening Developmental Questionnaire 2 (PDQ-II) in Tehran in comparison with the Denver Developmental Screening Test-II (DDST-II). METHODS: After translation and back translation, the final Persian version of test was verified by three pediatricians and also by reviewing relevant literature for content validity. The test was performed on 237 children ranging from 0 to 6 years old, recruited by convenient sampling, from four health care clinics in Tehran city. They were also evaluated by DDST II simultaneously. Interrater methods and Cronbach's α were used to determine reliability of the test. The Kappa agreement coefficient between PDQ and DDST II was determined. The data was analyzed by SPSS software. FINDINGS: All of the questions in PDQ had satisfactory content validity. The total Cronbach's α coefficient of 0-9 months, 9-24 months, 2-4 years and 4-6 years questionnaires were 0.951, 0.926, 0.950 and 0.876, respectively. The Kappa measure of agreement for interrater tests was 0.89. The estimated agreement coefficient between PDQ and DDST II was 0.383. Based on two different categorizing possibilities for questionable scores, that is, "Delayed" or "Normal", sensitivity and specificity of PDQ was determined to be 35.7-63% and 75.8-92.2%, respectively. CONCLUSION: PDQ has a good content validity and reliability and moderate sensitivity and specificity in comparison with the DDST-II, but by considering their relatively weak agreement coefficient, using it along with DDST-II for a two-stage developmental screening process, remains doubtful.
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INTRODUCTION: Ataxia telangiectasia (AT) is an autosomal recessive multisystem disorder characterized by variable immunodeficiency, progressive neurodegeneration, occulocutaneous telangiectasia, and an increased susceptibility to malignancies. This study was designed to study the role of proapoptotic BAK, BAX, and NBK/BIK genes in a group of patients with AT to elucidate the possible role of these genes in progression of malignancies in this disease. MATERIALS AND METHODS: Fifty Iranian patients with AT were investigated in this study. The entire coding regions of the BAK gene (exons 2-6), NBK/BIK gene (exons 2-5), and BAX gene (exons 1-7) were amplified using polymerase chain reaction (PCR). The PCR products were separated by 2% agarose gel electrophoresis, and all positive samples were verified by direct sequencing of PCR products using the same primers used for PCR amplification, BigDye chemistry, and Avent 3100 Genetic Analyzer following the manufacturer's instructions (Applied Biosystems). RESULTS: Eight of fifty Iranian AT patients (16%) exhibited a C > T transition in exon 2 (c342C > T) of the BAK gene, while none of the healthy controls had such alteration (P = 0.0001). Higher frequency of another nucleotide substitution in the noncoding region of exon 7 in BAX gene (6855G > A) was also identified in 68% of the patient group versus 24% in the controls (P < 0.0001). Sequence alteration in intronic region of the NBK/BIK gene IVS4-12delTC was observed in 52% of AT patients, which was significantly higher than 20% in the control group (P = 0.0023). Another variant IVS1146C > T in the intronic region of the BAX gene was found in 78% of patients, which was significantly higher than 10% in the controls (P < 0.0001). Frequency of alteration in intronic region of exon 3 of the BAX gene (IVS3 + 14A > G) was also significantly higher in the AT patients (P < 0.0001). DISCUSSION: Several alterations in the proapoptotic genes BAK, NBK/BIK, and BAX were found in our study, which could elucidate involvement of the mitochondrial pathway mediated apoptosis in accelerating and developing of cancers and in immunopathogenesis of AT. Such altered apoptosis in AT could play some roles in developing cancers in this group of patients.