Valosin-containing protein-regulated endoplasmic reticulum stress causes NOD2-dependent inflammatory responses.

NOD2 polymorphisms may affect sensing of the bacterial muramyl dipeptide (MDP) and trigger perturbed inflammatory responses. Genetic screening of a patient with immunodeficiency and enteropathy revealed a rare homozygous missense mutation in the first CARD domain of NOD2 (ENST00000300589; c.160G > A, p.E54K). Biochemical assays confirmed impaired NOD2-dependent signaling and proinflammatory cytokine production in patient's cells and heterologous cellular models with overexpression of the NOD2 mutant. Immunoprecipitation-coupled mass spectrometry unveiled the ATPase valosin-containing protein (VCP) as novel interaction partner of wildtype NOD2, while the binding to the NOD2 variant p.E54K was abrogated. Knockdown of VCP in coloncarcinoma cells led to impaired NF-κB activity and IL8 expression upon MDP stimulation. In contrast, tunicamycin-induced ER stress resulted in increased IL8, CXCL1, and CXCL2 production in cells with knockdown of VCP, while enhanced expression of these proinflammatory molecules was abolished upon knockout of NOD2. Taken together, these data suggest that VCP-mediated inflammatory responses upon ER stress are NOD2-dependent.

Prenatal Screening for Aneuploidies Using QF-PCR and Karyotyping: A Comprehensive Study in Iranian Population.

BACKGROUND: We have investigated the efficacy of QF-PCR for the prenatal recognition of common aneuploidy and compared our findings with cytogenetic results in our laboratories. METHODS: A total of 4058 prenatal samples (4031 amniotic fluid and 27 chorionic villous samples) were analyzed by QF-PCR using several selected STR markers together with amelogenin. Results were compared to those obtained by conventional cytogenetic analysis. RESULTS: We detected 139 (3.42%) numerical abnormalities in our subjects by QF-PCR. Concordant QF-PCR and karyotype results were obtained in 4001 (98.59%) of the samples. An abnormal karyotype associated with adverse clinical outcome undetected by QF-PCR was found in 16.66% (n = 28) of samples. Using QF-PCR alone, we were able to detect abnormalities in 98.59% of all referred families; however the karyotyping results improved the detection rate to 99.85% of the referred cases. Individuals with neonatal screening result with 1:10 risk ratio showed 11.29% abnormal karyotype while this number was 2.16% in mothers with risk ratio of 1:250 or less. CONCLUSION: In countries where large scale conventional cytogenetic is hampered by its high cost and lack of technical expertise, QF-PCR may be used as the first line of screening for detection of chromosomal abnormalities. We also recommend QF-PCR for all the families that are seeking prenatal diagnosis of single gene disorders aneuploidies screening to be added to their work up.

Investigation of microdeletions in syndromic intellectual disability by MLPA in Iranian population.

BACKGROUND: Intellectual Disabilities (ID), defined as a state of developmental deficit, result in significant limitation of intellect and poor adaptation behavior. A number of genetic factors can result in ID, such as chromosomal abnormalities, copy number variation, and single gene defect. Karyotyping is the routine method for detecting chromosomal abnormalities in patients with ID. More recently, the Multiplex Ligation-dependent Probe Amplification (MLPA) method has been applied for detecting microdeletion/duplication in patients with dysmorphism and ID. METHODS: A total of 100 patients with dysmorphism and ID have been referred to us since 2011. All patients were first evaluated clinically and a number of these individuals had normal karyotypes. We investigated duplications and deletions for 21 different microdeletion syndromes using MLPA kit (MRC-Holland). RESULTS: We were able to identify aberrations in 12 (12%) patients clinically ascertained as follows: 5 Williams syndromes, 3 Miller- Dieker syndromes, 1 Sotos syndrome, 1 Angelman Syndrome, 1 Di-George syndrome and one patient with an abnormal 4p chromosomal region. CONCLUSION: Our MLPA results indicate a high degree of concordance between the clinical data and the genotype. We suggest MLPA as the first screening method for children suffering from MR with normal karyotypes. In those cases where clinical findings were not compatible with the microdeletion syndrome identified by MLPA investigation, further studies such as FISH and aCGH were performed.