Investigation of the Genetic Etiology in Idiopathic Generalized Epileptic Disorders by Targeted Next-generation Sequencing Technique

Background

Idiopathic generalized epilepsy is the most common group of epilepsy disorders in children and adolescents. Various types of genetic abnormality were identified among the hereditary factors that explain epilepsy.

Aims

To determine the variations in the etiopathogenesis, treatment protocol planning, and prognosis of idiopathic generalized epilepsy using the next-generation sequencing method.

Study Design

A cross-sectional study.

Methods

This study included 32 patients with idiopathic generalized epilepsy. Genomic DNA was obtained from peripheral venous blood samples taken from the patients. A total of 18 genes encoding ion channel subunits that are involved in monogenic disorders and are associated with idiopathic generalized epilepsy were included. The targeted custom next-generation sequencing panel was designed to cover all coding exons and all exon/intron splice site regions of 18 genes.

Results

We detected 9 (28%) variations, including 1 likely pathogenic (a variant in the SCN1A gene) and 8 of unknown clinical significance (2 in the CLCN2 genes, GABBR2, SCN1B, SLC2A1, SLC4A10 genes, and 2 in the TBC1D24 gene).

Conclusion

Study results should be supported by functional advanced studies, with increased existing knowledge in the relevant variations.

A Case of Diabetes Mellitus Type MODY5 as a feature of 17q12 Deletion Syndrome

Maturity onset diabetes of the young (MODY) is characterized by noninsulin-dependent diabetes diagnosed at a young age (<25 years) with an autosomal dominant inheritence. Rare mutations in the hepatocyte nuclear factor-1-beta (HNF1B) gene produce a syndrome that resemble MODY and about half of patients diagnosed with MODY5 (HNF1B mutation) have a a whole gene deletion, called as 17q12 deletion syndrome, is a rare chromosomal anomaly and is typified by deletion of the more than 15 genes including HNF1B resulting in kidney abnormalities and renal cysts and diabetes syndrome and neurodevelepmental or neuropsychiatric disorders. A 12-year-old girl was referred to our clinic, after high blood sugar was detected in the hospital where she suffered with the complaints of poliuria and polydipsia for the last 1 month. Her serum magnessium level was low (1.5 mg/dl) (normal value 1.6-2.6) and HbA1c level was 14% (normal value 3.6-5.8) and c-peptide level was 1.54 ng/ml (normal value 0.8-4). MODY5 was suspected and followed NGS gene panel (ABCC8, BLK, CEL, GCK, HNF1A, HNF1B, HNF4A, INS, KCNJ11, KLF11, NEURODD1, PAX4, PDX1, RFX6, ZFP57, GLIS3, FOXP3, NEUROG3, G6PC2) analysis revealed that there was no any mutation. On follow-up period, her serum magnessium level was low (1.2 mg/dl) and her urinary magnessium excretion was high at 172.5 mg/day. HNF1B gene mutation was considered in the patient with chronic hypomagnesemia with increased basal C peptide level. Abdominal CT and MR imagings revealed that there was a 43 mm diameter cystic lesion in the head of the pancreas, and agenesis of the pancreatic neck, trunk and tail as well. Because of there is no mutation in HBF1B gene in NGS panel, microarray analysis was performed, heterozygous deletion at 17q12 including HNF1B was detected. The HNF1B mutation is difficult to diagnose and has a large phenotypic variation . In case of clinical suspicion,further genetic examination (MLPA, array CGH) may be required since deletions and duplications can not be detected even if mutations in the HNF1B gene are not detected with NGS.

The evaluation of risk factors leading to early deaths in patients with acute promyelocytic leukemia: a retrospective study

Acute promyelocytic leukemia (APL) differs from other forms of acute myeloid leukemia (AML), including coagulopathy, hemorrhage, disseminated intravascular coagulation (DIC), and treatment success with all-trans retinoic acid (ATRA). Despite ATRA, early deaths (ED) are still common in APL. Here, we evaluated factors associated with ED and applicability of scoring systems used to diagnose DIC. Ninety-one APL patients (55 females, 36 males, and median age 40 years) were included. ED was defined as deaths attributable to any cause between day of diagnosis and following 30th day. DIC was assessed based on DIC scoring system released by the International Society of Thrombosis and Hemostasis (ISTH) and Chinese Diagnostic Scoring System (CDSS). Patients' median follow-up time was 49.2 months, and ED developed in 14 (15.4% of) cases. Patients succumbing to ED had higher levels of the Eastern Cooperative Oncology Group Performance Status (ECOG PS), lactate dehydrogenase (LDH), and ISTH DIC, and lower fibrinogen levels (p <0.05). In multivariate Cox regression analysis, age >55 and ECOG PS ≥2 rates were revealed to be associated with ED. Based on ISTH and CDSS scores, DIC was reported in 47.3 and 58.2% of the patients, respectively. Despite advances in APL, ED is still a major obstacle. Besides the prompt recognition and correction of coagulopathy, those at high ED risk are recommended to be detected rapidly. Implementation of local treatment plans and creating awareness should be achieved in hematological centers. Common utilization of ATRA and arsenic trioxide (ATO) may be beneficial to overcome ED and coagulopathy in APL patients.

Comprehensive Genetic Analysis of RASopathy in the Era of Next-Generation Sequencing and Definition of a Novel Likely Pathogenic Variation

<b><i>Introduction:</i></b> Germline pathogenic variations of the genes encoding the components of the Ras-MAPK pathway are found to be responsible for RASopathies, a clinically and genetically heterogeneous group of diseases. In this study, we aimed to present the results of patients genetically investigated for RASopathy-related mutations in our Genetic Diagnosis Center. <b><i>Methods:</i></b> The results of 51 unrelated probands with RASopathy and 4 affected relatives (31 male, 24 female; mean age: 9.327 ± 8.214) were included in this study. Mutation screening was performed on DNA samples from peripheral blood of the patients either by Sanger sequencing of <i>PTPN11</i> hotspot regions (10/51 probands), or by a targeted amplicon next-generation sequencing panel (41/51 probands) covering the exonic regions of <i>BRAF</i>, <i>CBL</i>, <i>HRAS</i>, <i>KRAS</i>, <i>LZTR1</i>, <i>MAP2K1</i>, <i>MAP2K2</i>, <i>NF1</i>, <i>NRAS</i>, <i>PTPN11</i>, <i>RAF1</i>, <i>RASA2</i>, <i>RIT1</i>, <i>SHOC2</i>, <i>SOS1</i>, <i>SOS2</i>, <i>SPRED1</i>, and <i>KAT6B</i> genes. <b><i>Results:</i></b> Pathogenic/likely pathogenic variations found in 22 out of 51 probands (43.13%) and their 4 affected family members were located in <i>PTPN11</i>, <i>BRAF</i>, <i>KRAS</i>, <i>NF1</i>, <i>RAF1</i>, <i>SOS1</i>, and <i>SHOC2</i> genes. The c.148A&#x3e;C (p.Thr50Pro) variation in the <i>KRAS</i> gene was a novel variant detected in a sibling in our patient cohort. We found supportive evidence for the pathogenicity of the <i>NF1</i> gene c.5606G&#x3e;T (p.Gly1869Val) variation which we defined in an affected boy who inherited the mutation from his affected father. <b><i>Conclusion:</i></b> Although <i>PTPN11</i> is the most frequently mutated gene in our patient cohort, as in most previous reports, different mutation distribution among the other genes studied motivates the use of a next-generation sequencing gene panel including the possible responsible genes.

The efficiency of cinacalcet treatment in delaying parathyroidectomy in a case with neonatal severe hyperparathyroidism caused by homozygous mutation in the CASR gene

Neonatal severe hyperparathyroidism (NSHPT) causes severe hypercalcaemia, metabolic bone disease, and potential neurodevelopmental deficits, all of which can be life-threatening. The use of calcimimetic agents can prevent or delay technically difficult parathyroidectomy in the newborn period. We present a 6-day-old male infant who presented with poor feeding, weight loss, and severe hypotonia. His total serum calcium and parathyroid hormone levels were very high (23.6 mg/dl and 1120 ng/dl, respectively). Based on these findings, the patient was diagnosed with NSHPT and was started on cinacalcet therapy until the genetic analysis results were available. Genetic analysis revealed a previously reported homozygous mutation in the CASR gene that was unresponsive to cinacalcet therapy in the literature. However, a normocalcaemic state unexpectantly occurred, which could be maintained with low calcium formula and cinacalcet therapy up to 13 months of age in the patient. Nevertheless, hypercalcaemia developed 2 months after he started a normal calcium-containing diet. Therefore, the patient underwent total parathyroidectomy at 17 months of age. We would like to emphasize, in light of this case, that cinacalcet treatment may be considered as first-line therapy for delaying parathyroidectomy in all cases with NSHPT, even in those who have an unresponsive cinacalcet CASR gene mutation.

Comprehensive Genetic Analysis Results of TSC1/TSC2 Genes in Patients with Clinical Suspicion of Tuberous Sclerosis Complex and Definition of 3 Novel Variants

BACKGROUND

Tuberous Sclerosis Complex is an autosomal dominant multi-system disorder with an incidence of about 1 in 6000 live births. Defects in either TSC1 (* 605284) or TSC2 (* 191092) genes encoding the components of the Tuberous Sclerosis Complex are responsible for the disease. Therefore, consideration of TSC1/TSC2 pathogenic variations is recommended in the updated diagnostic criteria of Tuberous Sclerosis Complex.

AIMS

To present the TSC1/TSC2 screening results of a mixed patient population as well as possible new variants in 23 cases from 20 different families who were referred to our Genetic Diseases Diagnosis Center with the signs and symptoms of Tuberous Sclerosis Complex.

STUDY DESIGN

Retrospective, cross-sectional study.

METHODS

Germline TSC1/TSC2 variants were screened in DNA samples extracted from peripheral blood samples of 23 patients from 20 unrelated families using targeted high-throughput sequencing and multiplex ligation-dependent probe amplification methods. The variants identified were classified according to ACMG 2015 guidelines.

RESULTS

In total, 5 different pathogenic/likely pathogenic changes have been defined. All these pathogenic/likely pathogenic variants were located in the TSC2 gene. Three of the pathogenic/likely pathogenic variants were novel. Two patients who are twin sisters were found to have TSC2/PKD1 contiguous deletion syndrome. One of the 3 novel variants was a mosaic in-frame deletion. We did not identify any pathogenic variants of the TSC1 gene.

CONCLUSION

The novelty of most of the variants found, including a mosaic likely pathogenic variant, and the presence of a large genomic rearrangement, supports the importance of a comprehensive approach in analyzing TSC1/TSC2 genes. Genetic diagnosis should be performed with caution, considering the possibility of mosaic variants with low allelic fractions.

The Application of Next Generation Sequencing Maturity Onset Diabetes of the Young Gene Panel in Turkish Patients from Trakya Region

OBJECTIVE

The aim of this study was to investigate the molecular basis of maturity-onset diabetes of the young (MODY) by targeted-gene sequencing of 20 genes related to monogenic diabetes, estimate the frequency and describe the clinical characteristics of monogenic diabetes and MODY in the Trakya Region of Turkey.

METHODS

A panel of 20 monogenic diabetes related genes were screened in 61 cases. Illumina NextSeq550 system was used for sequencing. Pathogenicity of the variants were assessed by bioinformatics prediction software programs and segregation analyses.

RESULTS

In 29 (47.5%) cases, 31 pathogenic/likely pathogenic variants in the GCK, ABCC8, KCNJ11, HNF1A, HNF4A genes and in 11 (18%) cases, 14 variants of uncertain significance (VUS) in the GCK, RFX6, CEL, PDX1, KCNJ11, HNF1A, G6PC2, GLIS3 and KLF11 genes were identified. There were six different pathogenic/likely pathogenic variants and six different VUS which were novel.

CONCLUSION

This is the first study including molecular studies of twenty monogenic diabetes genes in Turkish cases in the Trakya Region. The results showed that pathogenic variants in the GCK gene are the leading cause of MODY in our population. A high frequency of novel variants (32.4%-12/37) in the current study, suggests that multiple gene analysis provides accurate genetic diagnosis in MODY.

Case Report

BACKGROUND

Thyroid hormone resistance (RTH) is defined as a decrease in response to thyroid hormones in the target tissue. Most patients present with nonspecific findings. In this article, we aimed to represent a 22-year-old female patient who presented with palpitation, fatigue, and heat intolerance. She was thought to have thyroid hormone resistance and her genetic examination revealed NM_001128177.1 (THRβ): c.1034G > A (p.Gly345Asp) pathogenic variation in the THRβ gene.

CASE REPORT

A 22-year-old female patient presented with complaints of fatigue, heat intolerance and palpitations. She was taking Propranolol twice daily at admission. Her family history revealed hypothyroidism in her grandmother. Her physical examination results were as follows: height 160 cm, weight 65 kg, body mass index 25.4kg/m², body temperature 36.5°C, respiratory rate 18/min, heart rate 86 beats/min, blood pressure 120/80 mmHg. Her palms were sweaty. The heart sounds were normal, and no heart murmur was auscultated. The laboratory results were TSH: 5.31uU/mL, fT3: 6.83 pg/mL, and fT4: 2.43 ng/dL. THRβ gene mutation analysis was requested for our patient whose clinical history and laboratory results were compatible with thyroid hormone resistance. The pathogenic variation NM_001128177.1(THRβ):c.1034G>A (p.Gly345Asp) was detected after analysis.

CONCLUSION

A diagnosis of RTH requires high clinical suspicion and a genetic mutation analysis should be requested in the case of clinical suspicion. In this way, unnecessary anti-thyroid treatment can be prevented.

Prenatal diagnosis of 20p13 microdeletion syndrome

OBJECTIVE

The objective of this study was to report the first case of prenatal diagnosis of the fetal 20p13 microdeletion syndrome in the literature.

CASE REPORT

The mother was 31 years old and had a first trimester serum screening that indicated the fetus was at low risk. The prenatal ultrasound at 23 weeks of gestation showed mild ventriculomegaly (10.2 mm) and absent septum pellucidum. She underwent amniocentesis because of the abnormal imaging results. Karyotype analysis revealed normal results. Chromosome microarray analysis (CMA) was then performed to provide genetic analysis of the fetus and parents. CMA detected 317.902 kb deletion of 20p13 in fetus. Finally, pregnancy was terminated at 32 weeks of gestation.

CONCLUSION

This study is the first to report the prenatal diagnosis of a 20p13 microdeletion syndrome. Our results further confirmed that genes in this region, including SOX12, NRSN2 are essential for normal fetal growth and TBC1D20 for normal brain development.

Targeted High-Throughput Sequencing Analysis Results of Osteogenesis Imperfecta Patients from Different Regions of Turkey

Objective: Osteogenesis imperfecta (OI) includes a group of disorders characterized by susceptibility to bone fractures with different severities. The increasing number of genes that may underlie the disorder, along with the broad phenotypic spectrum that overlaps with other skeletal diseases, provided a compelling case for the use of high-throughput sequencing (HTS) technology as an aid to OI diagnoses. The aim of this analysis was to present the data from our 5-year targeted HTS results, that includes the reporting of 9 novel and 24 known mutations, found in OI patients, from 5 different regions of Turkey. Materials and Methods: We performed a retrospective cross-sectional study, reporting the HTS results of 43 patients (23 female and 20 male; mean age: 9.5 years), directed to our center with a suspicion of OI between February 2015 and May 2020. Genetic analyses were also performed for 24 asymptomatic parents to aid the segregation analyses. We utilized an HTS panel targeting the coding regions of 57 genes associated with a reduction, increase, or abnormal development of bone mineralization. In addition, we sequenced the entire coding region of the IFITM5 gene through HTS. Results: Thirty-nine patients had at least one pathogenic/likely pathogenic variation (90.69%) in the COL1A1 (56.41%), COL1A2 (20.51%), FKBP10 (7.7%), P3H1 (5.13%), IFITM5 (5.13%), CTRAP (2.56%), or TMEM38B (2.56%) genes. Nine of the determined pathogenic/likely pathogenic variations were novel. The recurrent pathogenic mutations were c.1081C>T (p.Arg361Ter) (3/43), c.1405C>T (p.Arg469Ter) (2/43), and c.3749del (p.Gly1250AlafsTer81) in COL1A1 gene, along with c.-14C>T variation in the 5'UTR of the IFITM5 gene (2/43) and the c.890_897dup variation in the FKBP10 gene (2/43). Three out of 43 patients were carrying at least one additional variant of unknown significance, highlighting the importance of a multigene panel approach and segregation analyses. Conclusion: We suggest that a targeted HTS panel is a feasible tool for genetic diagnosis of OI in patients.

Wiedemann-Steiner Syndrome as a Differential Diagnosis of Cornelia de Lange Syndrome Using Targeted Next-Generation Sequencing: A Case Report

Wiedemann-Steiner syndrome (WDSTS) is a rare autosomal dominant disorder with a variable clinical phenotype including synophrys, hypertelorism, thick eyebrows, long eyelashes, wide nasal bridge, long philtrum, hypertrichosis, growth retardation, and intellectual disability. Cornelia de Lange syndrome (CdLS) is a rare disease characterized by synophrys, long eyelashes, limb abnormalities, generalized hirsutism, growth retardation, and intellectual disability. In both WDSTS and CdLS, the malformations are due to transcriptome disturbance caused by defects in the genes encoding the components of chromatin regulation and transcription process. The overlapping features in these two syndromes may complicate the original diagnosis of a patient. Here, we report on a Wiedemann-Steiner patient found to have a de novo pathogenic KMT2A variation who had been clinically suspected as CdLS. We suggest that targeted next-generation sequencing is a feasible tool for the precise diagnosis of patients who have phenotypically and clinically overlapping features of CdLS and WDSTS.

Chromosomal Microarray Analysis in Turkish Patients with Unexplained Developmental Delay and Intellectual Developmental Disorders

INTRODUCTION

Aneuploids, copy number variations (CNVs), and single nucleotide variants in specific genes are the main genetic causes of developmental delay (DD) and intellectual disability disorder (IDD). These genetic changes can be detected using chromosome analysis, chromosomal microarray (CMA), and next-generation DNA sequencing techniques. Therefore; In this study, we aimed to investigate the importance of CMA in determining the genomic etiology of unexplained DD and IDD in 123 patients.

METHOD

For 123 patients, chromosome analysis, DNA fragment analysis and microarray were performed. Conventional G-band karyotype analysis from peripheral blood was performed as part of the initial screening tests. FMR1 gene CGG repeat number and methylation analysis were carried out to exclude fragile X syndrome.

RESULTS

CMA analysis was performed in 123 unexplained IDD/DD patients with normal karyotypes and fragile X screening, which were evaluated by conventional cytogenetics. Forty-four CNVs were detected in 39 (39/123=31.7%) patients. Twelve CNV variant of unknown significance (VUS) (9.75%) patients and 7 CNV benign (5.69%) patients were reported. In 6 patients, one or more pathogenic CNVs were determined. Therefore, the diagnostic efficiency of CMA was found to be 31.7% (39/123).

CONCLUSION

Today, genetic analysis is still not part of the routine in the evaluation of IDD patients who present to psychiatry clinics. A genetic diagnosis from CMA can eliminate genetic question marks and thus alter the clinical management of patients. Approximately one-third of the positive CMA findings are clinically intervenable. However, the emergence of CNVs as important risk factors for multiple disorders increases the need for individuals with comorbid neurodevelopmental conditions to be the priority where the CMA test is recommended.

Is there an association between NC_012920.1: m.8277T> C mitochondrial variation the mt-NC7 locus, and migraine with aura?

BACKGROUND

The molecular basis of migraines is still not completely understood. Over the last 30 years, mitochondrial dysfunction has been postulated as a potential mechanism in migraine pathogenesis. This study aimed to determine whether maternal mitochondrial variation was associated with migraines with aura.

METHODS

In this cross-sectional study, 50 individuals, who had been diagnosed with migraines with aura between January 2016 and July 2018 in the Neurology Department of the University Medical Faculty, and 50 healthy controls were recruited. Genomic DNA was isolated from the Ethylenediaminetetraacetic acid (EDTA) blood samples of the patients and the controls using the Easy One automated DNA isolation system. Mitochondrial DNA (mtDNA) libraries were prepared according to the Nextera XT DNA library-preparation protocol, and they were sequenced on the MiSeq platform (Illumina Inc., San Diego, CA, USA).

RESULTS

In the patient and control groups' analysis, 13 mtDNA variations were determined to be significantly different (p <0.05). The CC genotype for NC_012920.1: m.8277T>C variation was found to be higher in the patient group than the control group (p =0.001). The mtDNA NC_012920.1: m.8277T>C variation was significantly associated with the presence of neurological disease in the patient's family (p =0.043).

CONCLUSIONS

The present study is the first to demonstrate an association between mitochondrial dysfunction and the susceptibility to migraine with aura in individuals carrying the NC_012920.1: m.8277T>C variation. Knowing the level of cytochrome C oxidase and oxidative phosphorylation corruption in these patients may be predictive in understanding the phenotype/genotype relationship. Thus, mtDNA variations may contribute to the pathogenesis of migraines with aura. HIPPOKRATIA 2020, 24(2): 59-65.

A novel LEMD3 pathogenic variant in a son and mother with osteopoikilosis

Elmaoğulları S, Yıldız AE, Demir S, Gürkan H, Uçaktürk SA. A novel LEMD3 pathogenic variant in a son and mother with osteopoikilosis. Turk J Pediatr 2019; 61: 594-598. Osteopoikilosis (OPK) is a rare, benign condition characterized by osteosclerotic foci that occur in the epiphyses and metaphyses of long bones, wrists, feet, ankles, pelvis, and scapulae. We report a 16-year-old boy and his mother incidentally found to have sclerotic lesions on X-ray. Both of them were asymptomatic and the bone scan of the boy ruled out osteoblastic metastases. We have shown that the boy and his mother have a previously unknown pathogenic variant of the LEMD3 gene, supporting the diagnosis of osteopoikilosis.

Chronic myeloid leukaemia after chemoradiotherapy for solid malignancies

Haematological malignancies associated with chemoradiotherapy (CRT) are often acute myeloid leukaemias and myelodysplastic syndromes. Chronic myeloid leukaemia (CML) has been reported rarely in these situations. Cytogenetics of CRT-associated CML is not different from de novo CML, and there are not enough data about its prognosis. We report two patients who had CRT because of lung cancer and squamous cell carcinoma of head and neck, who subsequently developed CML.

Genetic Diagnosis of Hereditary Hemorrhagic Telangiectasia: Four Novel Pathogenic Variations in Turkish Patients

Aims:

Hereditary hemorrhagic telangiectasia is an autosomal dominant disorder characterized by telangiectasia, epistaxis, and vascular malformations. Pathogenic mutations were found in ENG, AVCRL1, SMAD4, and GDF genes. In this study, we present our database of patients with hereditary hemorrhagic telangiectasia regarding the phenotype-genotype relations and discuss two novel ENG gene pathogenic variations in two unrelated families.

Methods:

Next Generation Sequencing analysis was performed on the peripheral blood of nine patients with hereditary hemorrhagic telangiectasia in four unrelated families. All patients were diagnosed with hereditary hemorrhagic telangiectasia according to the Curaçao criteria. Data on treatment and screenings of visceral involvement were recorded from files.

Results:

We have found a pathogenic variation in either the ENG or ACVRL1 gene in each family. Two novel pathogenic variations in the ENG gene, including NM_000118.3 (ENG): c.416delC (p.P139fs*24) and NM_000118.3(ENG): c.1139dupT (p.Leu380PhefsTer16), were found in the same family. The NM_000020.2(ACVRL1): c.1298C>T (p.Pro433Leu) pathogenic variation in the ACVRL1 gene in our first family and a novel heterozygous likely pathogenic NM_000020.2(ACVRL1): c.95T>C (p.Val32Ala) variation was found in our second family. Seven of the nine patients were treated with thalidomide for controlling bleeding episodes. All patients responded to thalidomide. In one patient, the response to thalidomide was lost and switched to bevacizumab.

Conclusion:

In hereditary hemorrhagic telangiectasia, certain types of mutations correlate with disease phenotypes and with next generation sequencing methods. New pathogenic variations can be revealed, which might help manage patients with hereditary hemorrhagic telangiectasia.

Investigation of Copy Number Variation by arrayCGH in Turkish Children and Adolescents Diagnosed with Autism Spectrum Disorders

Aim

The development of whole-genome screening methodologies for the detection of copy number variations (CNVs), such as array-based comparative genomic hybridization (aCHG), provides a much higher resolution than karyotyping leading to the identification of novel microdeletion and microduplication syndromes often associated with an autism spectrum disease (ASD) phenotype. The aim of the study was to determine CNVs of patients with ASD by using array-based comparative genomic hybridization.

Methods

Fifty-three patients diagnosed with ASD between 20.01.2014 and 14.01.2015 were included in the study. Chromosome analysis of the patients was performed from peripheral blood cultures and analysed as normal. All patients were evaluated with P064C1 and P096A2 MLPA probes in terms of 16 mental retardation related syndromes. For aCGH method, SurePrint G3 Human microarrays 8x60K were used with genomic DNA isolated from peripheral blood.

Results

According to results of 53 patients who were included in and performed with arrayCGH, 8 (15%) patients had CNVs classified as pathogenic or variant of unknown significance (VOUS) in the study. We detected a pathogenic NRXN1 gene partial CNV deletion (2p16.3) in two patients. Also we identified a 900 kb duplication of 4p15.31 including SLIT2 gene, and a 245 kb duplication of 15q11.2 including PWRN1 gene in one patient. Our other findings are considered to be a variant of unknown significance (VOUS).

Conclusion

The results of the study support the literature knowledge, where the copy number variations that cannot be detected with conventional cytogenetics methods in terms of size may happen in patients with ASD.

Investigation of IL23R, JAK2, and STAT3 gene polymorphisms and gene-gene interactions in Crohn's disease and ulcerative colitis in a Turkish population

BACKGROUND/AIMS

Inflammatory bowel diseases are chronic, relapsing, inflammatory conditions. They have a genetic backround resulting in patient susceptibility. The aim of our study is to investigate the involvement of IL23R, JAK2, and STAT3 polymorphisms in inflammatory bowel diseases in a Turkish population.

MATERIALS AND METHODS

Polymorphisms in IL23R (rs11209026), JAK2 (rs10758669), and STAT3 (rs3816769, rs2293152, rs744166, rs957970, rs8074524) were genotyped in 69 Crohn's disease patients, 157 ulcerative colitis patients, and 89 healthy controls.

RESULTS

The presence of (C) in rs10758669, (T) and (TT) in rs957970, and (TT) in rs744166 were found to increase the susceptibility to Crohn's disease (p=0.049, p=0.016, p=0.010, p=0.035, respectively), while rs2293152 (GC), rs744166 (CT), and rs957970 (CT) provide protection against Crohn's disease (p=0.007, p=0.043, p=0.043, respectively). While rs2293152 (GC) was protective, rs2293152 (CC) increased the susceptibility to ulcerative colitis (p=0.009, p=0.001). All the polymorphisms were associated with age-at-diagnosis, except rs11209026. Furthermore, rs2293152 was associated with an extension in ulcerative colitis, while rs10758669, rs3816769, rs744166, rs2293152, and rs957970 were associated with the subphenotype in Crohn's disease. The presence of rs10758669 (AC) was protective against perianal Crohn's disease (p=0.016). Additionally, rs10758669 and rs2293152 in Crohn's disease and rs8074524, rs3816769, and rs10758669 in ulcerative colitis were associated with the requirement of immunsuppression. Finally, rs8074524 and rs10758669 in Crohn's disease and rs11209026 in ulcerative colitis were associated with disease-related operation.

CONCLUSION

This is the first study of the single marker association of IL23R, JAK2, and STAT3 polymorphisms with ulcerative colitis and Crohn's disease in a Turkish population. It was demonstrated that these polymorphisms may be effective in the etiology of inflammatory bowel disease in this Turkish population.

Genetic Analyses of the NF1 Gene in Turkish Neurofibromatosis Type I Patients and Definition of three Novel Variants

Neurofibromatosis Type I (NF1) is a multi systemic autosomal dominant neurocutaneous disorder predisposing patients to have benign and/or malignant lesions predominantly of the skin, nervous system and bone. Loss of function mutations or deletions of the NF1 gene is responsible for NF1 disease. Involvement of various pathogenic variants, the size of the gene and presence of pseudogenes makes it difficult to analyze. We aimed to report the results of 2 years of multiplex ligation-dependent probe amplification (MLPA) and next generation sequencing (NGS) for genetic diagnosis of NF1 applied at our genetic diagnosis center. The MLPA, semiconductor sequencing and Sanger sequencing were performed in genomic DNA samples from 24 unrelated patients and their affected family members referred to our center suspected of having NF1. In total, three novel and 12 known pathogenic variants and a whole gene deletion were determined. We suggest that next generation sequencing is a practical tool for genetic analysis of NF1. Deletion/duplication analysis with MLPA may also be helpful for patients clinically diagnosed to carry NF1 but do not have a detectable mutation in NGS.

Lack of Association Between Toll-like Receptor 2 Polymorphisms (R753Q and A-16934T) and Atopic Dermatitis in Children from Thrace Region of Turkey

BACKGROUND

Atopic dermatitis is the most common chronic inflammatory skin disease. A complex interaction of both genetic and environmental factors is thought to contribute to the disease.

AIMS

To evaluate whether single nucleotide polymorphisms in the TLR2 gene c.2258C>T (R753Q) (rs5743708) and TLR2 c.-148+1614T>A (A-16934T) (rs4696480) (NM_0032643) are associated with atopic dermatitis in Turkish children.

STUDY DESIGN

Case-control study.

METHODS

The study was conducted on 70 Turkish children with atopic dermatitis aged 0.5-18 years. The clinical severity of atopic dermatitis was evaluated by the severity scoring of atopic dermatitis index. Serum total IgE levels, specific IgE antibodies to inhalant and food allergens were measured in both atopic dermatitis patients and controls, skin prick tests were done on 70 children with atopic dermatitis. Genotyping for TLR2 (R753Q and A-16934T) single nucleotide polymorphisms was performed in both atopic dermatitis patients and controls.

RESULTS

Cytosine-cytosine and cytosin-thymine genotype frequencies of the TLR2 R753Q single nucleotide polymorphism in the atopic dermatitis group were determined as being 98.6% and 1.4%, cytosine allele frequency for TLR2 R753Q single nucleotide polymorphism was determined as 99.29% and the thymine allele frequency was 0.71%, thymine-thymine, thymine-adenine, and adenine-adenine genotype frequencies of the TLR2 A-16934T single nucleotide polymorphism were 24.3%, 44.3%, and 31.4%. The thymine allele frequency for the TLR2 A-16934T single nucleotide polymorphism in the atopic dermatitis group was 46.43%, and the adenine allele frequency was 53.57%, respectively. There was not statistically significant difference between the groups for all investigated polymorphisms (p>0.05). For all single nucleotide polymorphisms studied, allelic distribution was analogous among atopic dermatitis patients and controls, and no significant statistical difference was observed. No homozygous carriers of the TLR2 R753Q single nucleotide polymorphism were found in the atopic dermatitis and control groups.

CONCLUSION

The TLR2 (R753Q and A-16934T) single nucleotide polymorphisms are not associated with atopic dermatitis in a group of Turkish patients.

A 9-year-old-girl with Phelan McDermid Syndrome, who had been diagnosed with an autism spectrum disorder

Phelan McDermid Syndrome (PHMDS) (OMIM #606232), is a contiguous gene disorder resulting from deletion of the distal long arm of chromosome 22. The 22q13.3 deletions and mutations that lead to a loss of a functional copy of SHANK3 (OMIM *606230) cause the syndrome, characterized by moderate to profound intellectual disability, severely delayed or absent speech, hypotonia, and autism spectrum disorder (ASD) or ASD traits. In this study, we present the case of a 9-year-old girl who had earlier been diagnosed with an ASD. Our findings were a clinically mild intellectual disability, rounded face, pointed chin but no autistic findings. We learned that her neuromotor development was delayed and she had neonatal hypotonia in her history. A heterozygous deletion of MLC1, SBF1, MAPK8IP2, ARSA, SHANK3 and ACR genes, located on 22q13.33, was defined by multiplex ligation-dependent probe amplification (MLPA). Deletion of 22q13.3 (ARSA) region was confirmed by a fluorescent in situ hybridization (FISH) technique. The 22q13.3 deletion was found to be de novo in our patient, and she was diagnosed with PHMDS. We confirmed the 22q13.3 deletion and also determined a gain of 8p23.3-23.2 by array comparative genomic hybridization (aCGH). Fluorescent in situ hybridization was performed to determine whether the deletion was of parental origin and to identify regions of chromosomes where the extra 8p may have been located. The parents were found to be normal. The extra copy of 8p was observed on 22q in the patient. She is the first case reported in association with the 22q deletion of 8p duplications in the literature.

KRAS Mutation in Small Cell Lung Carcinoma and Extrapulmonary Small Cell Cancer

BACKGROUND

Lung cancer is one of the most lethal cancers. It is mainly classified into 2 groups: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Extrapulmonary small cell carcinomas (EPSCC) are very rare. The Ras oncogene controls most of the cellular functions in the cell. Overall, 21.6% of human cancers contain a Kirsten Ras (KRAS) mutation. SCLC and EPSCC have several similar features but their clinical course is different.

AIMS

We investigated the KRAS mutation status in SCLC and EPSCC.

STUDY DESIGN

Mutation research.

METHODS

Thirty-seven SCLC and 15 EPSCC patients were included in the study. The pathological diagnoses were confirmed by a second pathologist. KRAS analysis was performed in our medical genetic department. DNA isolation was performed with primary tumor tissue using the QIAamp DNA FFPE Tissue kit (Qiagen; Hilden, Germany) in all patients. The therascreen KRAS Pyro Kit 24 V1 (Qiagen; Hilden, Germany) was used for KRAS analyses.

RESULTS

Thirty-four (91.9%) of the SCLC patients were male, while 11 (73.3%) of the EPSCC l patients were female. SCLC was more common in males, and EPSCC in females (p=0.001). A KRAS mutation was found in 6 (16.2%) if SCLC patients. The most common mutation was Q61R (CAA>CGA). Among the 15 EPSCC patients, 2 had a KRAS mutation (13.3%). When KRAS mutant and wild type patients were compared in the SCLC group, no difference was found for overall survival (p=0.6).

CONCLUSION

In previous studies, the incidence of KRAS mutation in SCLC was 1-3%; however, it was 16.2% in our study. Therefore, there may be ethnic and geographical differences in the KRAS mutations of SCLC. As a result, KRAS mutation should not be excluded in SCLC.

A case with Emanuel syndrome: extra derivative 22 chromosome inherited from the mother

Emanuel syndrome (ES) is a rare chromosomal disorder that is characterized by multiple congenital anomalies and developmental disabilities. Affected children are usually identified in the newborn period as the offspring of balanced (11;22) translocation carriers. Carriers of this balanced translocation usually have no clinical symptoms and are often identified after the birth of offspring with an unbalanced form of the translocation, the supernumerary der(22) t(11;22) syndrome. We report a 3-year-old boy with the t(11;22)(q23;q11) chromosome, transmitted in an unbalanced fashion from his mother. He has several developmental delays; he is not independently ambulatory and language is significantly impaired. Using his peripheral blood, karyotyping was performed to define his multiple congenital anomalies, revealing the following chromosomal abnormality: 47, XY, +der(22)t(11;22)(q23.3;q11.2). To ascertain the origin and trait of this supernumerary marker chromosome [der(22)t(11;22)(q23.3;q11.2)], karyotyping of his parents was performed. The mother was found to be a balanced carrier: 46, XX, t(11;22) (q23.3; q11.2).

Tyrosine kinase-2 gene polymorphisms are associated with ulcerative colitis and Crohn's disease in Turkish Population

BACKGROUND AND OBJECTIVE

Inflammatory bowel disease is a group of chronic inflammatory conditions affecting gastrointestinal tract. Lots of genes have been identified resulting in susceptibility to inflammatory bowel disease. Any polymorphism leading to functional modifications in tyrosine kinase-2 may precipitate excessive immune response in the intestinal mucosa. The aim of our study is to investigate the involvement of tyrosine kinase-2 polymorphisms in the patients with inflammatory bowel disease in Turkish population.

METHODS

Four single nucleotide polymorphisms in tyrosine kinase-2 (rs280523, rs2304256, rs280519 and rs280496) were genotyped in 60 Crohn's disease, 151 ulcerative colitis patients and 89 unrelated healthy controls. These polymorphisms were detected by real-time polymerase chain reaction.

RESULTS

The presence of genotype (CC) in rs2304256 and (AA) in rs280519 were found to increase the susceptibility to ulcerative colitis (P=0.024, 0.025, respectively). rs2304256 (CA) and rs280519 (AG) have provided protection against ulcerative colitis (P=0.021, 0.012, respectively). rs280519 (AG) was protective against Crohn's disease (P=0.045). rs2304256 (CC) increased the susceptibility to inflammatory Crohn's disease (P=0.014). The presence of rs2304256 (A) increased the susceptibility to perianal Crohn's disease (P=0.03). Both rs280519 and rs2304256 polymorphisms were associated with the requirement of corticosteroid and immunosuppressive therapy in ulcerative colitis.

CONCLUSION

This study is the first demonstration of the single marker association of tyrosine kinase-2 polymorphisms with ulcerative colitis and Crohn's disease in Turkish population. They may be effective in the etiology of inflammatory bowel disease in our population. Disparity between our study and others may be related to ethnic differences.

Identification of a novel HLA-A*26 allele, HLA-A*26:01:36, in a Turkish family by sequence-based typing

HLA-A*26:01:36 differs from the closest allele HLA-A*26:01:01 by a nucleotide change at the position 114.

A novel biometric authentication approach using electrocardiogram signals

In this work, we present a novel biometric authentication approach based on combination of AC/DCT features, MFCC features, and QRS beat information of the ECG signals. The proposed approach is tested on a subset of 30 subjects selected from the PTB database. This subset consists of 13 healthy and 17 non-healthy subjects who have two ECG records. The proposed biometric authentication approach achieves average frame recognition rate of %97.31 on the selected subset. Our experimental results imply that the frame recognition rate of the proposed authentication approach is better than that of ACDCT and MFCC based biometric authentication systems, individually.

Results of Mitochondrial DNA Sequence Analysis in Patients with Clinically Diagnosed Leber's Hereditary Optic Neuropathy

OBJECTIVE

To investigate possible mitochondrial DNA (mtDNA) mutations in patients with Leber's hereditary optic neuropathy (LHON) in order to provide a precise diagnosis and genetic counseling.

MATERIAL AND METHODS

Between 1982 and 2007, ten patients were clinically diagnosed with LHON and six of these patients agreed to be involved in this study. Six healthy individuals were also included as a control group. mtDNA was isolated from peripheral blood samples and polymerase chain reaction and mtDNA sequence analysis were performed.

RESULTS

In one of the six patients, a homoplasmic mutant m.11778G>A mutation was detected. All of the clinically diagnosed LHON patients and the control groups had the m.14212C>T and m.14580G>A single nucleotide polymorphisms (SNPs). The m.11719A>G SNP was detected in three of six patients and four of the controls. Two of the six patients had the m.3197T>C SNP and, in addition, the m.14258G>A SNP was found in one of these two patients, while neither of these mutations were present in the control group.

CONCLUSION

The clinical diagnosis of LHON could be supported by molecular genetics only in one patient by the detection of one mutation. The m.3197T>C and m.14258G>A SNPs should be considered as potential mtDNA mutations due to the fact that they were detected in the patient group. These mutations should be investigated further in large case groups for suspected gene loci that could lead to optic neuropathy.

The presence of donor-specific antibodies in renal transplantation

Determining the presence of anti-HLA antibodies before transplantation is an important factor to prevent loss of function among renal transplantations. In addition, recent studies have shown that not only the pretransplantation existence of anti-HLA antibody but also posttransplantation donor-specific antibodies (DSA) and non-donor-specific antibodies are significantly associated with allograft rejection or loss of graft function. This study presented DSA among patients after renal transplantation together with graft function and survival.

Comparison of lipid profiles with APOA1 MspI polymorphism in obese children with hyperlipidemia

BACKGROUND

Obesity is a multifactorial, chronic disorder leading to adverse metabolic effects on plasma lipid levels. Apolipoprotein AI (Apo AI) is the major structural component of high-density lipoprotein (HDL) and is involved in the esterification of cholesterol as a cofactor of lecithin-cholesterol acyltransferase (LCAT) and thus plays a major role in cholesterol efflux from peripheral cells. The APOA1 gene is associated with changes in lipid metabolism. A common gene polymorphism described in the APOA1 promoter region consists of the exchange of guanine (G) for adenine (A) at a position -75 bp upstream of the transcription origin. The relationship between lipid levels in obese children and the APOA1 MspI polymorphisms, was examined.

MATERIALS AND METHODS

Three separate groups were included, the patient group of obese children with hyperlipidemia; the obese control group (control group I) consisted of obese children without hyperlipidemia; and the healthy control group (control group II) contained healthy children with neither hyperlipidemia nor obesity. The related gene segments were amplified by polymerase chain reaction and determined different patterns were determined using denaturating gradient gel electrophoresis and positive results were confirmed automatic sequence analysis. All the results were analyzed by Proseq and BioEdit computer programmes.

RESULTS

The A allele was found to be more frequent in control group I compared to the patient group (p=0.035). Very low-density lipoprotein (VLDL), LDL and triglyceride (TG), levels were statistically higher in the patients carrying the GA genotype than in control group I, and body mass index (BMI), VLDL and TG levels were statistically higher than in control group II (p<0.05). There was no relationship between -75(G/A) polymorphism and serum lipid HDL-cholesterol levels when patient values were compared to those of the controls (p>0.05). Additionally, according to the -75 GA genotypes, those in control group I with the GA genotype had elevated total cholesterol levels compared to those with the GG genotype (p<0.010). In conclusion, carrying the A allele could confer a higher risk of hyperlipidemia in obese children.

Streptomycin sulphate microspheres: dissolution rate studies and release kinetics. I

Targeting of drugs by microspheres, nanoparticles and liposomes is intended to increase the selective targeting to specific organs and to reduce their side effects. Streptomycin sulphate, a tuberculostatic antibiotic, is used as the active principle in this study. The aim is to accumulate the loaded microspheres in the lungs. The release of drugs associated with microsphere carriers has been found to be dependent on a number of factors. The aim of the investigation was to study the influence of the extent and nature of cross-linking, the type and the amount of the matrix material on the release characteristics of streptomycin sulphate microspheres. Human serum albumin and gelatin (Type B) were used as two different matrix materials. The crosslinking agents used were 2,3-butanedione and formaldehyde at different concentrations, and variable duration times. The in vitro release of streptomycin sulphate from microspheres is characteristically biphasic, with an initial fast release (the 'burst effect'), followed by a much slower release. Alteration in the characteristics of drug-loaded microspheres result in significant changes in the second (slow) phase of release. The release profiles of the different formulations has been studied and evaluated kinetically.

Streptomycin sulphate microspheres: formulation and in vivo distribution

Albumin and gelatin microspheres of streptomycin sulphate were formulated and their potential as a drug delivery system for a tuberculostatic agent in vivo was evaluated. Biodistribution was determined by i.v. administration of a 99mTc-labelled microsphere suspension to mice. The radioactivity of the lungs was compared with the radioactivity of the liver, spleen, kidney and heart at 10 min, 60 min, 4 h and 24 h post-injection. The percentage accumulated was higher in the lungs than in the other organs for both albumin and gelatin microspheres.

Epilepsia partialis continua following pertussis infection

Clinical, electrophysiological and CT findings of a patient with epilepsia partialis continua following pertussis infection are presented. The EEG showed lateralized abnormal slow waves and CT revealed global atrophy around the Sylvian fissure. The findings favor the primary role of the cerebral cortex in EPC.