Unveiling New Clinical and Genetic Insights in Ultra-Rare Intellectual Disability Phenotypes: A Study of a Turkish Cohort.

Intellectual disability (ID) is defined as a severe impairment in reasoning, learning, and problem-solving abilities along with adaptive behavior that occurs before the age of 18 years. The present study aimed to present the clinical and genetic data of a cohort of Turkish pediatric patients diagnosed with the ultrarare (which only up to 20 cases having been reported in the relevant literature thus far) ID phenotype. A total of 29 patients from 26 different families, who were diagnosed with ultrarare ID upon whole exome sequencing (WES) analysis, were included in the study.

Comparison of Clinical and Genetic Characteristics of Familial Mediterranean Fever Patients Among Adult Age Groups.

Familial mediterranean fever (FMF) is a genetic autoinflammatory disease typically diagnosed in childhood. In this study, we aimed to investigate the demographic, clinical, and genetic characteristics of patients aged 18 years and older who were diagnosed with FMF. Patients diagnosed with FMF between 2014 and 2022 at Karadeniz Technical University Faculty of Medicine Hospital were included in the study.

Secondary findings in genes related to cancer phenotypes in Turkish exome sequencing data from 2020 individuals.

Big data generated from exome sequencing (ES) and genome sequencing (GS) analyses can be used to detect actionable and high-penetrance variants that are not directly associated with the primary diagnosis of patients but can guide their clinical follow-up and treatment. Variants that are classified as pathogenic/likely pathogenic and are clinically significant but not directly associated with the primary diagnosis of patients are defined as secondary findings (SF). The aim of this study was to examine the frequency and variant spectrum of cancer-related SF in 2020 Turkish ES data and to discuss the importance of the presence of cancer-related SF in at-risk family members in terms of genetic counseling and follow-up.

A Homozygous Missense Variant in Identified in Two Different Families.

Background: Perrault syndrome is an inherited disorder with clinical findings that differ according to sex. It is characterized by a variable age of onset and sensorineural hearing loss in both sexes, as well as ovarian dysfunction in females with a 46,XX karyotype. Although it is a rare autosomal recessive syndrome, with approximately 100 affected individuals reported in the literature, it shows both genotypic and phenotypic variations.

The first Turkish family with a novel biallelic missense variant of the ALKBH8 gene: A study on the clinical and variant spectrum of ALKBH8-related intellectual developmental disorders.

ABH8, the protein encoded by the ALKBH8 gene, modifies tRNAs by methylating their anticodon wobble uridine residues. The variations in the ALKBH8 gene are associated with the "intellectual developmental disorder, autosomal recessive type 71" (MIM: 618504) phenotype in the OMIM database. This phenotype is characterized by global developmental delay, facial dysmorphic features, and psychiatric problems.

Prediction of molecular phenotypes for novel SCN1A variants from a Turkish genetic epilepsy syndromes cohort and report of two new patients with recessive Dravet syndrome.

Dravet syndrome and genetic epilepsy with febrile seizures plus (GEFS+) are both epilepsy syndromes that can be attributed to deleterious mutations occurring in SCN1A, the gene encoding the pore-forming α-subunit of the Na 1.1 voltage-gated sodium channel predominantly expressed in the central nervous system. In this research endeavor, our goal is to expand our prior cohort of Turkish patients affected by SCN1A-positive genetic epilepsy disorders.

Primary Immunodeficiencies in Children Initially Admitted with Gastrointestinal/Liver Manifestations.

Purpose: The gastrointestinal system is the most commonly affected organ, followed by the lungs, in patients with primary immunodeficiency disease (PID). Hence, it is common for children with PIDs to present with gastrointestinal symptoms. We aimed to analyze the clinical and histopathological findings of patients who were initially admitted to pediatric gastroenterology/hepatology clinics and subsequently diagnosed with PIDs to identify the clinical clues for PIDs.

De novo Pure Partial Trisomy 6p Associated with Facial Dysmorphism, Developmental Delay, Brain Anomalies, and Primary Congenital Hypothyroidism.

Introduction: Partial trisomy 6p is a rare chromosomal anomaly, characterized by low birth weight, developmental delay, craniofacial abnormalities, feeding difficulties, congenital heart defects, and renal abnormalities. Some of the partial trisomy 6p cases reported in the literature included partial monosomy of another chromosome. This is often due to the fact that one of the parents is a balanced translocation carrier, thereby making it difficult to determine the genotype-phenotype relationship.

Autosomal Recessive Primary Microcephaly (MCPH) and Novel Pathogenic Variants in and Genes.

Introduction: Autosomal recessive primary microcephaly (MCPH) is a disorder characterized by congenital microcephaly and intellectual disability without extra-central nervous system malformation. MCPH is a disease with heterogeneity in genotype and phenotype. For this reason, it is important to determine the genetic causes and genotype-phenotype relationship in MCPH, which causes lifelong impairment.

Having Multiple Renal Cysts in a Young Adult is not Always a Sign of Polycystic Kidney Disease.

Multiple renal cysts in adult patients could have asymptomatic, benign and a nonprogressive course. However, these cysts could be renal features of a very rare hereditary, progressive syndrome defined as cranioectodermal dysplasia (CED or Sensenbrenner syndrome). Affected patients show dysmorphic features such as craniosynostosis, nail dystrophy, cutaneous dyshydrosis, dry or scaly palmar skin, trichodysplasia, deafness, pectus excavatum, telecanthus, hypertelorism, low set ears, everted lower lip, anteverted nares, short neck and height, joint laxity, inguinal hernia, widely spaced teeth, microdontia, hypodontia in addition to nephronophthisis.

Array-Based Comparative Genomic Hybridization Analysis in Children with Developmental Delay/Intellectual Disability.

Developmental delay (DD) is a condition wherein developmental milestones and learning skills do not occur at the expected age range for patients under 5 years of age. Intellectual disability (ID) is characterized by limited or insufficient development of mental abilities, including intellectual functioning impairments, such as learning and cause-effect relationships. Isolated and syndromic DD/ID cases show extreme genetic heterogeneity.

Genetic Landscape of Variants in a Turkish Cohort with GEFS+ Spectrum and Dravet Syndrome.

Introduction: The α subunit of voltage-gated sodium channels in mammals is encoded by 9 different genes, and variations in the , , , and genes highly expressed in the CNS have been associated with epilepsy phenotypes. This study aimed at investigating the frequency of gene variations in Dravet syndrome (DS) and GEFS+ spectrum phenotype cases and discussing the molecular results in the context of genotype-phenotype correlation.

Methods: Fifteen patients diagnosed with DS and 54 patients meeting the GEFS+ spectrum criteria were included in this study.

Molecular characterization of Turkish patients with demyelinating Charcot-Marie-Tooth disease.

Charcot-Marie-Tooth (CMT) disease represents a distinct subgroup of inherited peripheral neuropathies with a significant prevalence throughout the world and manifests both phenotypic and genetic heterogeneity. Electrophysiological studies subclassify CMT mainly as demyelinating or axonal types. In this study, we investigated the molecular characteristics of a Turkish cohort of 23 probands out of 34 symptomatic demyelinating CMT individuals from January 2019 to December 2021.

Familial Hemophagocytic Lymphohistiocytosis With Heterozygous STX11 and Homozygous UNC13D Mutations Diagnosed in the Neonatal Period.

Patients with primary hemophagocytic lymphohistiocytosis may present with different mutations and phenotypic findings. It is usually presented as case reports because of its rare occurrence. Here, we discuss a case diagnosed with familial hemophagocytic lymphohistiocytosis 3, that presented in the neonatal period and was detected to have homozygous UNC13D and heterozygous STX11 mutations.

Whole-exome sequencing reveals new potential genes and variants in patients with premature ovarian insufficiency.

Purpose: Premature ovarian insufficiency (POI) is a heterogeneous disorder characterized by the cessation of menstrual cycles before the age of 40 years due to the depletion or dysfunction of the ovarian follicles. POI is a highly heterogeneous disease in terms of etiology. The aim of this study is to reveal the genetic etiology in POI patients.

Early onset congenital diarrheas; single center experience.

Background: Congenital diarrheal disorders (CDDs) are a rare group of enteropathies that typically present in the early few months of life and pose a diagnostic challenge. We aimed to analyze the clinical findings and outcome of infants with CDDs and share experience about genetic testing.

Methods: Demographic, clinical and genetic findings, and outcome of the patients (n = 24) with CDDs were recorded from hospital files.

Secondary findings in 622 Turkish clinical exome sequencing data.

CES (Clinical Exome Sequencing) is a method that we use to diagnose rare diseases with nonspesific clinical features. Besides primary indication for testing genetic information may be detected about diseases which have not yet emerged. ACMG guidelines recommend to report pathogenic variations in medically actionable 59 genes.

Immune Dysregulation, Polyendocrinopathy, Enteropathy, X-linked Syndrome in Two Siblings: Same Mutation But Different Clinical Manifestations at Onset.

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is an early onset systemic autoimmune genetic disorder caused by mutation of the gene. Enteropathy, endocrinopathy and skin manifestations are considered the classic triad of IPEX syndrome. However, patients with IPEX syndrome display a variety of phenotypes including life threatening multi-organ autoimmunity.

Application of Chromosome Microarray Analysis in the Investigation of Developmental Disabilities and Congenital Anomalies: Single Center Experience and Review of and Deletions.

Chromosomal microarray analysis (CMA) is a first step test used for the diagnosis of patients with developmental delay, intellectual disability, autistic spectrum disorder, and multiple congenital anomalies. Its widespread usage has allowed genome-wide identification of copy number variations (CNVs). In our study, we performed a retrospective study on clinical and microarray data of 237 patients with developmental disabilities and/or multiple congenital anomalies and investigated the clinical utility of CMA.

Plasma microRNA levels in childhood IgA vasculitis.

Introduction: Immunoglobulin A vasculitis (IgAV) is the most common form of childhood systemic vasculitis. It is mostly self-limiting and characterized by skin, joint, gastrointestinal tract, and kidney involvement. Microribonucleic acids (miRNAs) are 18-25 base-long non-coding RNA group acting on gene expression.