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Introduction: Interleukin-1 receptor antagonist deficiency is a rare autoinflammatory disease involving neonatal onset of pustulosis, periostitis, and sterile osteomyelitis. The underlying genetic abnormality involves a recessive mutation in IL1RN, which encodes interleukin-1 receptor antagonist. In this case report, we describe a case of a 12-year-old Turkish girl who initially was presented at 1 year of age, older than previously reported children with interleukin-1 receptor antagonist deficiency, and with a novel mutation, p.R26X, in ILR1N. Case presentation: Our patient developed pustular cutaneous lesions at 1 year of age. At the age of 12 years, she was hospitalized for arthralgia of her knees, elbows, and ankles and arthritis of the left knee, with simultaneous pustular cutaneous lesions. She was admitted to the intensive care unit because of septicemia and respiratory insufficiency during follow-up. A skin biopsy of hyperpigmented lesions demonstrated neutrophil infiltration in the epidermis and subepidermal pustular dermatosis. Interleukin-1 receptor antagonist deficiency was suspected, and genetic analysis revealed a homozygous mutation (p.R26X) in IL1RN, which led to a diagnosis of interleukin-1 receptor antagonist deficiency. Treatment with canakinumab (recombinant human anti-human interleukin-1β monoclonal antibody) 150mg subcutaneously once every 6 weeks was initiated. Our patient did not experience further cutaneous lesions or arthritis. Her post-treatment inflammatory markers were normal; she gained weight; and she was able to walk independently. Conclusions: In this case report, we describe a patient with interleukin-1 receptor antagonist deficiency who responded excellently to canakinumab treatment. We believe more awareness is warranted for interleukin-1 receptor antagonist deficiency in children. It is possible that the mutation in our patient was a founder mutation that may lead to diagnosis of additional cases in Turkey. [ABSTRACT FROM AUTHOR]

Hyperimmunoglobulinemia D Syndrome (HIDS) has rarely been reported in Arabs. Moreover, the simultaneous presence of mutations in MEFV and MVK segregating in the same family is exceptional. We report an Arabic girl presenting since the age of 8-years with two patterns of recurrent episodes of fever, and associated with a spectrum of clinical features suggestive of overlap between familial Mediterranean fever (FMF) and HIDS. Her 19-year old brother presented since the age of 1 year with prolonged episodes of fever and was diagnosed with HIDS at the age of 7 years based on clinical features and homozygosity for p.V377I mutation in MVK. Shorter episodes of fever and abdominal pain more consistent with FMF ensued since the age of 17 years. Genetic testing done for both patients and all other family members revealed simultaneous presence of mutations in MEFV and MVK but with a variable clinical spectrum ranging from asymptomatic to severe manifestations. Both of our patients are homozygous for p.V377I MVK mutation; the girl is a compound heterozygote for p.E148Q/p.P369S/p.R408G and p.E167D/p.F479L MEFV mutations whereas the brother is a compound heterozygote for p.E148Q/p.P369S/p.R408G and p.M680I MEFV mutations. The clinical implications of having more than one mutation in different genes of monogenic autoinflammatory diseases in the same individual are not clear but may explain atypical clinical manifestations such as the overlap features of both FMF and HIDS in this family. [ABSTRACT FROM AUTHOR]

Epilepsy is a common disabling disease with complex, multifactorial genetic and environmental etiology. The small fraction of epilepsies subject to Mendelian inheritance offers key insight into epilepsy disease mechanisms; and pathologies brought on by mutations in a single gene can point the way to generalizable therapeutic strategies. Mutations in the PRICKLE genes can cause seizures in humans, zebrafish, mice, and flies, suggesting the seizure-suppression pathway is evolutionarily conserved. This pathway has never been targeted for novel anti-seizure treatments. Here, the mammalian PRICKLE-interactome was defined, identifying prickle-interacting proteins that localize to synapses and a novel interacting partner, USP9X, a substrate-specific de-ubiquitinase. PRICKLE and USP9X interact through their carboxy-termini; and USP9X de-ubiquitinates PRICKLE, protecting it from proteasomal degradation. In forebrain neurons of mice, USP9X deficiency reduced levels of Prickle2 protein. Genetic analysis suggests the same pathway regulates Prickle-mediated seizures. The seizure phenotype was suppressed in prickle mutant flies by the small-molecule USP9X inhibitor, Degrasyn/WP1130, or by reducing the dose of fat facets a USP9X orthologue. USP9X mutations were identified by resequencing a cohort of patients with epileptic encephalopathy, one patient harbored a de novo missense mutation and another a novel coding mutation. Both USP9X variants were outside the PRICKLE-interacting domain. These findings demonstrate that USP9X inhibition can suppress prickle-mediated seizure activity, and that USP9X variants may predispose to seizures. These studies point to a new target for anti-seizure therapy and illustrate the translational power of studying diseases in species across the evolutionary spectrum. [ABSTRACT FROM AUTHOR]

Background A consanguineous Arab family is affected by an apparently novel autosomal recessive disorder characterized by cognitive impairment, failure-to-thrive, hypotonia and dysmorphic features including bilateral ptosis and epicanthic folds, synophrys, midface hypoplasia, downturned mouth corners, thin upper vermillion border and prominent ears, bilateral 5th finger camptodactyly, bilateral short 4th metatarsal bones, and limited knee mobility bilaterally. Methods The family was studied by homozygosity mapping, candidate gene mutation screening and whole Exome Next Generation Sequencing of a single affected member to identify the offending gene and mutation. The mutated gene product was studied by structural bioinformatics methods. Results A damaging c.C5054G mutation affecting an evolutionary highly conserved amino acid p.S1685W was identified in the ZNF407 gene at 18q23. The Serine to Tryptophane mutation affects two of the three ZNF407 isoforms and is located in the last third of the protein, in a linker peptide adjoining two zinc-finger domains. Structural analyses of this mutation shows disruption of an H-bond that locks the relative spatial position of the two fingers, leading to a higher flexibility of the linker and thus to a decreased probability of binding to the target DNA sequence essentially eliminating the functionality of downstream domains and interfering with the expression of various genes under ZNF407 control during fetal brain development. Conclusions ZNF407 is a transcription factor with an essential role in brain development. When specific and limited in number homozygosity intervals exist that harbor the offending gene in consanguineous families, Whole Exome Sequencing of a single affected individual is an efficient approach to gene mapping and mutation identification. [ABSTRACT FROM AUTHOR]

Objective Monogenic autoinflammatory diseases are disorders of Mendelian inheritance that are characterized by mutations in genes that regulate innate immunity and whose typical features are systemic inflammation without high-titer autoantibodies or antigen-specific T cells. Skin and bone inflammation in the newborn period have been described in 3 of these autoinflammatory disorders: neonatal-onset multisystem inflammatory disease, Majeed syndrome, and deficiency of interleukin-1 (IL-1) receptor antagonist (DIRA) syndrome. This study was undertaken to present the characteristics of the DIRA syndrome in 2 cases from Brazil, and describe a novel mutation in IL1RN. Methods Two unrelated Brazilian patients were evaluated for the clinical signs and symptoms of these 3 disorders, and peripheral blood samples were assessed for mutations in NLRP3, LPIN2, and IL1RN by DNA resequencing analysis. A mutation in IL1RN that encodes a mutant protein was identified, and the expression and function of this mutant protein were compared to those of the wild-type protein. Results Both patients presented with pustular dermatitis resembling generalized pustular psoriasis, recurrent multifocal aseptic osteomyelitis, and elevation in the levels of acute-phase reactants, all of which are features most consistent with the DIRA syndrome. Chronic lung disease was observed in 1 of the patients, and jugular venous thrombosis was observed in the other patient. Both patients showed a partial response to corticosteroid therapy, and 1 patient experienced an initial improvement of dermatitis with the use of acitretin. Both patients were homozygous for a novel 15-bp (in-frame) deletion on the IL1RN gene. The mutated protein expressed in vitro had no affinity with the IL-1 receptor, and stimulation of the patients' cells with recombinant human IL-1α or IL-1β led to oversecretion of proinflammatory cytokines, similar to the findings obtained in previously reported patients. Conclusion The presence of the same homozygous novel mutation in IL1RN in 2 unrelated Brazilian patients suggests that this genetic variant may be a founder mutation that has been introduced in the Brazilian population. [ABSTRACT FROM AUTHOR]

Objectives. FMF is characterized by recurrent self-limiting episodes of fever and painful polyserositis. We aimed to study the spectrum and distribution of MEFV mutations in an Algerian patient cohort using a comprehensive mutation detection method. Using the same methodology, we also studied the carrier rate in an unaffected ethnically matched control cohort.Methods. We recruited 71 unrelated subjects clinically diagnosed with FMF from various clinics in the central region of Algeria. Two hundred and thirty control subjects were recruited as well. Mutation detection in MEFV was performed by re-sequencing the promoter region, the entire coding sequence and all exon–intron boundaries.Results. We detected eight different mutations located in exons 10 (p.M694I, p.M694V, p.A744S, p.M680I, p.I692Del), 9 (p.I591T), 3 (p.P369S/p.R408Q) and 2 (p.E148Q). Out of the 71 patients, 31 carried at least one mutation. While the 71 patients are expected to have 142 mutant chromosomes, only 50 were identified. p.M694I (17.6%) is the most common mutation, followed by p.M694V (5%), p.E148Q (4.2%), p.A744S (3.5%) and p.M680I (3%). One novel variant was identified in the promoter region in the heterozygous state in three patients and in two controls. The carrier rate of the identifiable mutations is estimated to be 1 : 5.Conclusion. This study describes the MEFV mutational spectrum and distribution in the Algerian population. It shows that p.M694I is the most common MEFV mutation in Algerians. It also shows that, similar to other Arabic populations, <50% of mutant chromosomes are identified, even when employing comprehensive strategies. [ABSTRACT FROM PUBLISHER]

Chronic recurrent multifocal osteomyelitis is an autoinflammatory disorder characterized by bone pain and fever, a course of exacerbations and remissions, and a frequent association with other inflammatory conditions. Because its etiology is largely unknown, the diagnosis is still based on clinical criteria; treatment is empiric and not always successful. The diagnosis is supported by the presence of osteolytic lesions with surrounding sclerosis apparent on radiographs, and silent asymptomatic lesions frequently appear on nuclear scans. The histologic findings in bone biopsies are nonspecific, showing inflammatory changes with granulocytic infiltration. Several observations suggest the contribution of genetic factors to the etiology of chronic recurrent multifocal osteomyelitis. Indeed, mutations in LPIN2 cause a syndromic form of chronic recurrent multifocal osteomyelitis known as Majeed syndrome, while mutations in pstpip2 cause a murine form of the disorder. The roles played by LPIN2 and the human homolog of pstpip2, PSTPIP2, in the etiology of chronic recurrent multifocal osteomyelitis are uncertain but are currently being investigated. We emphasize the need to validate diagnostic clinical criteria and develop new pathogenesis-based targeted therapy. [ABSTRACT FROM AUTHOR]

The article describes the case of a three-year-old Arabic girl who had Majeed syndrome. As a neonate, the patient had hepatosplenomegaly and anemia. Information regarding the patient's laboratory test results is given. A DNA sequencing method was used for the coding regions and splice sites of LPIN2 gene in the patient and her unaffected mother. The study detected a homozygous single-basepair change in the 5' splice site of exon 17 in the patient.

Members of the CCN (for CTGF, cyr61/cef10, nov) gene family encode cysteine-rich secreted proteins with roles in cell growth and differentiation. Cell-specific and tissue-specific differences in the expression and function of different CCN family members suggest they have non-redundant roles. Using a positional-candidate approach, we found that mutations in the CCN family member WISP3 are associated with the autosomal recessive skeletal disorder progressive pseudorheumatoid dysplasia (PPD; MIM 208230). PPD is an autosomal recessive disorder that may be initially misdiagnosed as juvenile rheumatoid arthritis. Its population incidence has been estimated at 1 per million in the United Kingdom, but it is likely to be higher in the Middle East and Gulf States. Affected individuals are asymptomatic in early childhood. Signs and symptoms of disease typically develop between three and eight years of age. Clinically and radiographically, patients experience continued cartilage loss and destructive bone changes as they age, in several instances necessitating joint replacement surgery by the third decade of life. Extraskeletal manifestations have not been reported in PPD. Cartilage appears to be the primary affected tissue, and in one patient, a biopsy of the iliac crest revealed abnormal nests of chondrocytes and loss of normal cell columnar organization in growth zones. We have identified nine different WISP3 mutations in unrelated, affected individuals, indicating that the gene is essential for normal post-natal skeletal growth and cartilage homeostasis. [ABSTRACT FROM AUTHOR]

The T-13910 variant located in the enhancer element of the lactase (LCT) gene correlates perfectly with lactase persistence (LP) in Eurasian populations whereas the variant is almost nonexistent among Sub-Saharan African populations, showing high prevalence of LP. Here, we report identification of two new mutations among Saudis, also known for the high prevalence of LP. We confirmed the absence of the European T-13910 and established two new mutations found as a compound allele: T/G-13915 within the -13910 enhancer region and a synonymous SNP in the exon 17 of the MCM6 gene T/C-3712, -3712 bp from the LCT gene. The compound allele is driven to a high prevalence among Middle East population(s). Our functional analyses in vitro showed that both SNPs of the compound allele, located 10 kb apart, are required for the enhancer effect, most probably mediated through the binding of the hepatic nuclear factor 1 α (HNF1α). High selection coefficient (s) ~0.04 for LP phenotype was found for both T-13910 and the compound allele. The European T-13910 and the earlier identified East African G-13907 LP allele share the same ancestral background and most likely the same history, probably related to the same cattle domestication event. In contrast, the compound Arab allele shows a different, highly divergent ancestral haplotype, suggesting that these two major global LP alleles have arisen independently, the latter perhaps in response to camel milk consumption. These results support the convergent evolution of the LP in diverse populations, most probably reflecting different histories of adaptation to milk culture. [ABSTRACT FROM AUTHOR]

A single missense mutation was identified in a novel, highly conserved zinc-finger gene, ZCD2, in three consanguineous families of Jordanian descent withWolfram syndrome (WFS). It had been shown that these families did not have mutations in the WFS1 gene (WFS1) but were mapped to the WFS2 locus at 4q22-25. A G→C transversion at nucleotide 109 predicts an amino acid change from glutamic acid to glutamine (E37Q). Although the amino acid is conserved and the mutation is nonsynonymous, the pathogenesis for the disorder is because the mutation also causes aberrant splicing. The mutation was found to disrupt messenger RNA splicing by eliminating exon 2, and it results in the introduction of a premature stop codon. Mutations in WFS1 have also been found to cause low-frequency nonsyndromic hearing loss, progressive hearing loss, and isolated optic atrophy associated with hearing loss. Screening of 377 probands with hearing loss did not identify mutations in the WFS2 gene. The WFS1-encoded protein,Wolframin, is known to localize to the endoplasmic reticulum and plays a role in calcium homeostasis. The ZCD2-encoded protein, ERIS (endoplasmic reticulum intermembrane small protein), is also shown to localize to the endoplasmic reticulum but does not interact directly withWolframin. Lymphoblastoid cells from affected individuals show a significantly greater rise in intracellular calcium when stimulated with thapsigargin, compared with controls, although no difference was observed in resting concentrations of intracellular calcium. [ABSTRACT FROM AUTHOR]