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Chromosome 16 is one of the gene-rich chromosomes; however, approximately 10% of the chromosome 16 sequence is composed of segmental copies, which renders this chromosome instable and predisposes it to rearrangements via frequent nonallelic homologous recombination. Microarray technologies have enabled the analysis of copy number variations (CNV), which may be associated with the risk of developing complex diseases. Through comparative genomic hybridisation in 1,298 patients, we detected 18 cases with chromosome 16 CNV. We identified 2recurrent CNV regions, including 1 at 16p13.11 in 4 patients and another at 16p11.2 in 7 patients. We also detected atypical chromosome 16 rearrangements in 7 patients. Furthermore, we noted an increased frequency of co-occurring genomic changes, supporting the two-hit hypothesis to explain the phenotypic variability in the clinical presentation of CNV syndromes. Our findings can contribute to the creation of a chromosome 16 disease map based on regions that may be associated with disease development.

Jacobsen syndrome is a rare congenital disorder that is caused by the deletion of several genes in chromosome 11. A 10-year-old female with congenital heart disease, dextrocardia, and coarse facial appearance was examined in our medical genetics clinic. Chromosome analysis and array-CGH showed a copy number loss of 9 Mb in the 11q24.2q25 region. Herein, we report her clinical findings. This is the first case of Jacobsen syndrome with dextrocardia.

Duplications of 6q and deletions of 6p have been reported in more than 30 cases of live born infants and given rise to widespread abnormalities recognizable as a specific clinical syndrome. Different phenotypes have been described with variable clinical signs. Most cases involve the coexistence of unbalanced translocations affecting one or the other of the chromosomes. However, duplication of both chromosome 6q and deletion of 6p regions have been reported in only a few cases. Here, we report the first duplication of chromosome band 6q23.3–q27 with deletion of 6p25.3. This is the first case in the literature involving changes to these specific chromosomal regions; a medium size duplication of the distal long arm and smaller deletion of the terminal short arm of chromosome 6. In the literature, there are no other cases where these two specific chromosomal aberrations are observed together. Conventional chromosome analysis was performed to investigate the patient. Chromosome structure was identified using fluorescence in situ hybridization for subtelomeric regions of chromosome 6 and array comparative genomic hybridization analysis (array-CGH).

Introduction Autism spectrum disorder is a genetically and phenotypically heterogeneous group. Genetic studies carried out to date have suggested that both common and rare genetic variants play a role in the etiology of this disorder. In our study, we aimed to investigate the effect of FOXP2, GRIN2B, KATNAL2 and GABRA4 gene variants in the pathogenesis of autism spectrum disorder. Method In our prospectively planned study, all exons and exon-intron junctions of FOXP2, GRIN2B, KATNAL2 and GABRA4 genes were screened by next generation sequencing analysis in 96 patients who diagnosed with autism spectrum disorder. Results In our study, the average age was 10.1 and the male/female ratio was 75/21. Pathogenic or likely pathogenic variants were not detected in FOXP2, GRIN2B, KATNAL2 and GABRA4 genes, however, 69 intronic variants of unknown clinical significance were detected in 50 cases (52%). Among those, 26 were in the GABRA4 gene, 22 in the FOXP2 gene, 13 in the KATNAL2 gene, and 8 in the GRIN2B gene. Twenty three of these 69 variants were novel that were not previously reported in the literature. Conclusion In our study, we could not identify a relationship between the autism spectrum disorder and FOXP2, GRIN2B, KATNAL2 and GABRA4 genes. Identifying genetic risk factors that play a role in the etiopathogenesis of autism spectrum disorder will contribute significantly to understanding the molecular mechanisms of the disease and the development of new treatment strategies. In this context, comprehensive molecular genetic studies such as whole exome or whole genome sequencing are required with higher number of cases in different populations.

The early fusion of the cranial sutures was described as a craniosynostosis. The early diagnosis and management of craniosynostosis is very important. Environmental factors and genetic abnormalities plays a key role during the development of craniosynostosis. Syndromic craniosynostosis cases are related with autosomal dominant disorders but nearly half of the affected cases carry a new mutation. In this study, in order to identify the genetic etiology of craniosynostosis the authors analyzed 20 craniosynostosis patients by using conventional karyotype, aCGH, sanger sequencing, next generation sequencing (NGS) and Multiplex ligation-dependent probe amplification (MLPA) techniques. The authors identified mutations on FGFR2 and FGFR3 genes which were associated with Muenke syndrome, Crouzon syndrome and skeletal dysplasia syndromes. NGS applied all of the cases and 7 clinical variations in 5 different gene were detected in %20 of cases. In addition to these abnormalities; del(11)(q14.1q22.2), del(17)(q21.31), dup(22)(q13.31) and t(2;16)(q37;p13) have been identified in our cohort which are not previously detected in craniosynostosis cases. Our study demonstrates the importance of detailed genetic analysis for the diagnosis, progression and management of the craniosynostosis.

Introduction: Advanced diagnostic methods give a huge advantage for identification of the abnormalities in myeloid malignancies. Researchers tried to show the potential importance of genetic tests both before the onset of the disease and during the remission. Large testing panels prevents false negative results in myeloid malignancies. But the important question is how can be merged with conventional cytogenetic and molecular cytogenetic techniques together with NGS technologies. Methods: In this paper, we draw an algorithm for evaluation of the malignancies. In order to evaluation of genetic abnormities we performed cytogenetics, molecular cytogenetics and NGS testing panels in hematologic malignancies. In this study, we analyzed 132 patients which are referred to Medical Genetics Laboratory within different type of hematologic malignancies. We highlighted possible algorithm for cytogenetically normal cases.Results: We analyzed cytogenetically normal patients by using NGS 141 gene panel and we detected two or more pathogenic variations in 20 out of 132 patients.Conclusions: Despite of long turnaround time conventional techniques is still golden standard for myeloid malignancies but sometimes cryptic gene fusions or complex abnormalities cannot easily be identified by conventional techniques that conditions advanced technologies are recommended.

Risk assessment in newly diagnosed multiple myeloma patients (NDMM) is the first and the most crucial determinant of treatment. With the utilization of FISH analysis as a part of routine practice, high risk Multiple Myeloma (MM) is defined as having at least one of the mutations related with poor prognosis including; t(4;14) t(14;16), t(14;20), del 17p, p53 mutation, gain 1q and del 1p. M-Smart MM risk stratification guideline by Mayo Clinic has proposed a concept similar to high grade lymphomas. Having two of the high risk genetic abnormalities were defined as double hit MM and having any three as triple hit MM. Based on these definitions which may bring a much more clinically relatable understanding in MM prognosis, we aimed to assess our database regarding these two concepts and their probable significance in terms of outcome and prognosis. We retrospectively evaluated 159 newly diagnosed multiple myeloma patients and their clinical course. Among these patients; twenty-four patients have one high risk determinant and also seven and two patients were classified as double hit MM and triple hit MM respectively. Overall survival (OS) of the patients with double hit MM was 6 months, 32.0 months for patients with single high risk abnormality and 57.0 months for patients with no high risk abnormality. Univariate analysis showed that Double Hit and Triple Hit MM is a predictive of low OS. Hazard Ratio of patients with one high risk abnormality was 1.42, double-hit MM patients was 5.55, and triple-hit MM patients was 7.3. Despite the development of novel drugs and their effects of prolonging survival, the treatment has not been individualized. Understanding the biology of each patient as a unique process will be the success of the treatment. As it is known that some MM patients harbor high risk genetic abnormalities according to FISH analysis, we can continue the argument that some patients bring an even higher risk and that can be defined as double or triple hit MM.