Genetic insights into fetal kidney development: Variants in HNF1A and PKHD1 genes.

The orchestration of fetal kidney development involves the precise control of numerous genes, including HNF1A, HNF1B and PKHD1. Understanding the genetic factors influencing fetal kidney development is essential for unraveling the complexities of renal disorders. This study aimed to search for disease-causing variants in HNF1A, HNF1B, PKHD1 genes, among fetus and babies or via parental samples, using sanger sequencing, NGS technologie and MLPA.

Variants in SART3 cause a spliceosomopathy characterised by failure of testis development and neuronal defects.

Squamous cell carcinoma antigen recognized by T cells 3 (SART3) is an RNA-binding protein with numerous biological functions including recycling small nuclear RNAs to the spliceosome. Here, we identify recessive variants in SART3 in nine individuals presenting with intellectual disability, global developmental delay and a subset of brain anomalies, together with gonadal dysgenesis in 46,XY individuals. Knockdown of the Drosophila orthologue of SART3 reveals a conserved role in testicular and neuronal development.

Molecular mechanisms underlying the defects of two novel mutations in the HSD17B3 gene found in the Tunisian population.

17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) converts Δ4-androstene-3,17-dione (androstenedione) to testosterone. It is expressed almost exclusively in the testes and is essential for appropriate male sexual development. More than 70 mutations in the HSD17B3 gene that cause 17β-HSD3 deficiency and result in 46,XY Disorders of Sex Development (46,XY DSD) have been reported.

Li-Fraumeni syndrome in Tunisian carriers with different and rare tumor phenotype: genotype-phenotype correlation.

Background: Li-Fraumeni syndrome (LFS) is a rare autosomal hereditary predisposition to multiples cancers, mainly affecting young individuals. It is characterized by a broad tumor spectrum. To our best knowledge, only one Tunisian study with a confirmed LFS was published.

Autosomal dominant polycystic kidney disease (ADPKD) in Tunisia: From molecular genetics to the development of prognostic tools.

A high prevalence of genetic kidney disease in Tunisia has been detected, and their study provides very important clinical and genetic information. Autosomal dominant polycystic kidney disease (ADPKD) is one of the main causes of morbidity and mortality associated with the kidneys in Tunisia. We present here clinical and genetic characteristics of a cohort of Tunisian patients with ADPKD.

Annexin A1 and its receptor gene polymorphisms in systemic lupus erythematosus in the Tunisian population.

Background: An association between ANXA1, FPR1 and FPR2 gene polymorphisms and the patho-physiology of many human diseases was suggested by numerous studies.

Objective: Our study aimed to evaluate association between common polymorphisms in the 9q21.13 and 19q13.

Occurrence of Hypopituitarism in Tunisian Turner Syndrome patients: familial versus sporadic cases.

Objective: To explore unusual association between Turner Syndrome (TS) and Hypopituitarism in a Tunisian cohort.

Methods: We reported 6 patients with TS associated to Hypopituitarism, including three familial cases except the fourth sister who showed only a TS phenotype. Biochemical analysis, resonance magnetic imaging and cytogenetic analyses were performed.

High Diagnostic Yield of Targeted Next-Generation Sequencing in a Cohort of Patients With Congenital Hypothyroidism Due to Dyshormonogenesis.

Objective: To elucidate the molecular cause in a well-characterized cohort of patients with Congenital Hypothyroidism (CH) and Dyshormonogenesis (DH) by using targeted next-generation sequencing (TNGS).

Study Design: We studied 19 well-characterized patients diagnosed with CH and DH by targeted NGS including genes involved in thyroid hormone production. The pathogenicity of novel mutations was assessed based on prediction tool results, functional studies when possible, variant location in important protein domains, and a review of the recent literature.

SRD5A3-CDG: 3D structure modeling, clinical spectrum, and computer-based dysmorphic facial recognition.

Pathogenic variants in Steroid 5 alpha reductase type 3 (SRD5A3) cause rare inherited congenital disorder of glycosylation known as SRD5A3-CDG (MIM# 612379). To date, 43 affected individuals have been reported. Despite the development of various dysmorphic features in significant number of patients, facial recognition entity has not yet been established for SRD5A3-CDG.

Detection of a novel mutation in a Tunisian child with polycystic kidney disease.

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is the most common monogenic disease that has an adverse impact on the patients' health and quality of life. ADPKD is usually known as "adult-type disease," but rare cases have been reported in pediatric patients. We present here a 2-year-old Tunisian girl with renal cyst formation and her mother with adult onset ADPKD.

Mutations in GAA Gene in Tunisian Families with Infantile Onset Pompe Disease: Novel Mutation and Structural Modeling Investigations.

Pompe disease, a rare, autosomal, recessive, inherited, lysosomal storage disorder, is caused by mutations in the acid α-glucosidase (GAA) gene leading to a deficiency of the lysosomal GAA enzyme. Some GAA mutations eliminate all enzymatic activities, causing severe infantile Pompe disease; others allow residual GAA activity and lead to middle adulthood forms. Here, we report a cohort of 12 patients, belonging to 11 unrelated families, with infantile Pompe disease.

Copy-number variation of the NPHP1 gene in patients with juvenile Nephronophthisis.

: Juvenile nephronophthisis (NPHP) is an autosomal recessive cystic disease of the kidney. It represents the most frequent genetic cause of chronic renal failure in children. : we investigated clinical and molecular features in two children with Juvenile nephronophthisis using firstly Multiplex ligation-dependent probe amplification (MLPA) and secondly multiplex PCR.

A novel de novo splicing mutation c.1444-2A>T in the TSC2 gene causes exon skipping and premature termination in a patient with tuberous sclerosis syndrome.

Tuberous sclerosis complex (TSC) syndrome is a neurocutaneous syndrome that affects the brain, skin, and kidneys that has an adverse impact on the patient's health and quality of life. There have been several recent advances that elucidate the genetic complex of this disorder that will help understand the basic neurobiology of this disorder. We report a Tunisian patient with clinical manifestations of TSC syndrome.

Mutational analysis in patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD): Identification of five mutations in the PKD1 gene.

Autosomal Dominant Polycystic Kidney Disease (ADPKD), the most frequent genetic disorder of the kidneys, is characterized by a typical presenting symptoms include cysts development in different organs and a non-cysts manifestations. ADPKD is caused by mutations in PKD1 or PKD2 genes. In this study, we aimed to search for molecular causative defects among PKD1 and PKD2 genes.

Thyroid Hypoplasia in Congenital Hypothyroidism Associated with Thyroid Peroxidase Mutations.

Background: Primary congenital hypothyroidism (CH) affects about 1:3000 newborns worldwide and is mainly caused by defects in thyroid gland development (thyroid dysgenesis [TD]) or hormone synthesis. A genetic cause is identified in <10% of TD patients. The aim was to identify novel candidate genes in patients with TD using next-generation sequencing tools.

ZNRF3 functions in mammalian sex determination by inhibiting canonical WNT signaling.

Mammalian sex determination is controlled by the antagonistic interactions of two genetic pathways: The SRY-SOX9-FGF9 network promotes testis determination partly by opposing proovarian pathways, while RSPO1/WNT-β-catenin/FOXL2 signals control ovary development by inhibiting SRY-SOX9-FGF9. The molecular basis of this mutual antagonism is unclear. Here we show that ZNRF3, a WNT signaling antagonist and direct target of RSPO1-mediated inhibition, is required for sex determination in mice.

First description of a novel mitochondrial mutation in the MT-TI gene associated with multiple mitochondrial DNA deletion and depletion in family with severe dilated mitochondrial cardiomyopathy.

Mitochondria are essential for early cardiac development and impaired mitochondrial function was described associated with heart diseases such as hypertrophic or dilated mitochondrial cardiomyopathy. In this study, we report a family including two individuals with severe dilated mitochondrial cardiomyopathy. The whole mitochondrial genome screening showed the presence of several variations and a novel homoplasmic mutation m.

First report of an unusual novel double mutation affecting the transcription repression domain of MeCP2 and causing a severe phenotype of Rett syndrome: Molecular analyses and computational investigation.

Rett syndrome is an X-linked neurodevelopmental disorder that develops a profound intellectual and motor disability and affects 1 from 10 000 to 15 000 live female births. This disease is characterized by a period of apparently normal development until 6-18 months of age when motor and communication abilities regress which is caused by mutations occurred in the X-linked MECP2 gene, encoding the methyl-CpG binding protein 2. This research study reports a molecular analysis via an exhaustive gene sequencing which reveals an unusual novel double mutation (c.

Novel cases of Tunisian patients with mutations in the gene encoding 17β-hydroxysteroid dehydrogenase type 3 and a founder effect.

17β-Hydroxysteroid dehydrogenase type 3 (17β-HSD3) is expressed almost exclusively in the testis and converts Δ4-androstene-3,17-dione to testosterone. Mutations in the HSD17B3 gene causing 17β-HSD3 deficiency are responsible for a rare recessive form of 46, XY Disorders of Sex Development (46, XY DSD). We report novel cases of Tunisian patients with 17β-HSD3 deficiency due to previously reported mutations, i.

First molecular diagnosis of Donohue syndrome in Africa: novel unusual insertion/deletion mutation in the INSR gene.

Donohue syndrome (DS) is a very rare autosomal recessive disease affecting less than one in a million life births. It represents the most severe form of insulin resistance due to mutations involving the insulin receptor (IR) gene "INSR". DS is characterized by pre- and postnatal growth retardation with failure-to-thrive, lipoatrophy, acanthosis nigricans, hypertrichosis, and dysmorphic features.

Biochemical analyses and molecular modeling explain the functional loss of 17β-hydroxysteroid dehydrogenase 3 mutant G133R in three Tunisian patients with 46, XY Disorders of Sex Development.

Mutations in the HSD17B3 gene resulting in 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) deficiency cause 46, XY Disorders of Sex Development (46, XY DSD). Approximately 40 different mutations in HSD17B3 have been reported; only few mutant enzymes have been mechanistically investigated. Here, we report novel compound heterozygous mutations in HSD17B3, composed of the nonsense mutation C206X and the missense mutation G133R, in three Tunisian patients from two non-consanguineous families.