HomSI software is freely available at www.igbam.bilgem.tubitak.gov.tr/softwares/HomSI, with an online manual.

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Vascular malformations are non-neoplastic expansions of blood vessels that arise due to errors during angiogenesis. They are a heterogeneous group of sporadic or inherited vascular disorders characterized by localized lesions of arteriovenous, capillary, or lymphatic origin. Vascular malformations that occur inside bone tissue are rare. Herein, we report loss-of-function mutations in ELMO2 (which translates extracellular signals into cellular movements) that are causative for autosomal-recessive intraosseous vascular malformation (VMOS) in five different families. Individuals with VMOS suffer from life-threatening progressive expansion of the jaw, craniofacial, and other intramembranous bones caused by malformed blood vessels that lack a mature vascular smooth muscle layer. Analysis of primary fibroblasts from an affected individual showed that absence of ELMO2 correlated with a significant downregulation of binding partner DOCK1, resulting in deficient RAC1-dependent cell migration. Unexpectedly, elmo2-knockout zebrafish appeared phenotypically normal, suggesting that there might be human-specific ELMO2 requirements in bone vasculature homeostasis or genetic compensation by related genes. Comparative phylogenetic analysis indicated that elmo2 originated upon the appearance of intramembranous bones and the jaw in ancestral vertebrates, implying that elmo2 might have been involved in the evolution of these novel traits. The present findings highlight the necessity of ELMO2 for maintaining vascular integrity, specifically in intramembranous bones.

Stromme syndrome is a rare genetic disorder characterized by microcephaly, anterior ocular chamber anomalies, and "apple peel" type jejunal atresia. Here, we report a Stromme syndrome family with two affected siblings with a homozygous truncating frameshift mutation in CENPF. A 3-month-old girl was hospitalized due to prenatally diagnosed microcephaly, microphthalmia, and dysmorphological features. The history of a previous child with the same findings in addition to "apple peel" intestinal atresia had been noted. Regarding the clinical features of both affected siblings, a diagnosis of Stromme syndrome was established. Exome-sequencing of these two cases showed the homozygous mutation (c.5912_5913insA)/(p.T1974Nfs*9) in CENPF. While confirmation of this gene being responsible for Stromme syndrome was pending our results, Filges et al. reported that CENPF was indeed underlying the reason for Stromme syndrome. This is the second case report identifying CENPF mutation as the cause of Stromme syndrome.

DOCK7 (MIM:615730) plays a key role in neurogenesis by promoting the differentiation and transition of radial glial cells to basal progenitors and neurons [1]. DOCK7 also regulates tangential neuroblast migration in the postnatal mouse forebrain [2]. Recently, a new phenotype of early infantile epileptic encephalopathies (EIEE23, MIM: 615859) was reported in 3 girls from 2 families with 4 different compound heterozygous truncating mutations in DOCK7 [3]. Here, we report a boy with infantile onset well-controlled non-encephalopathic epilepsy and severe neurodevelopmental delay associated with a novel homozygous truncating mutation in DOCK7.

This study aimed to identify PYGM mutations in patients with McArdle disease from Turkey by next generation sequencing (NGS). Genomic DNA was extracted from the blood of the McArdle patients (n=67) and unrelated healthy volunteers (n=53). The PYGM gene was sequenced with NGS and the observed mutations were validated by direct Sanger sequencing. A diagnostic algorithm was developed for patients with suspected McArdle disease. A total of 16 deleterious PYGM mutations were identified, of which 5 were novel, including 1 splice-site donor, 1 frame-shift, and 3 non-synonymous variants. The p.Met1Val (27-patients/11-families) was the most common PYGM mutation, followed by p.Arg576* (6/4), c.1827+7A>G (5/4), c.772+2_3delTG (5/3), p.Phe710del (4/2), p.Lys754Asnfs (2/1), and p.Arg50* (1/1). A molecular diagnostic flowchart is proposed for the McArdle patients in Turkey, covering the 6 most common PYGM mutations found in Turkey as well as the most common mutation in Europe. The diagnostic algorithm may alleviate the need for muscle biopsies in 77.6% of future patients. A prevalence of any of the mutations to a geographical region in Turkey was not identified. Furthermore, the NGS approach to sequence the entire PYGM gene was successful in detecting a common missense mutation and discovering novel mutations in this population study.

Neuronal ceroid lipofuscinosis (NCL), one of the most common neurodegenerative childhood-onset disorders, is characterized by autosomal-recessive inheritance, epileptic seizures, progressive psychomotor deterioration, visual impairment, and premature death. Based on the country of origin of the patients, the clinical features/courses, and the molecular genetics background of the disorder, 14 distinct NCL subtypes have been described to date. CLN8 mutation was first identified in Finnish patients, and the condition was named Northern Epilepsy (NE); however, the severe phenotype of the CLN8 gene was subsequently found outside Finland and named 'variant late-infantile' NCL. In this study, five patients and their six healthy relatives from a large Turkish consanguineous family were enrolled. The study involved detailed clinical, radiological and molecular genetic evaluations. Whole-exome sequencing and homozygosity mapping revealed a novel homozygous CLN8 mutation, c.677T>C (p.Leu226Pro). We defined NE cases in Turkey, caused by a novel mutation in CLN8. WES can be an important diagnostic method in rare cases with atypical courses.

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