RESUMO
Neurodevelopmental delay and intellectual disability (ID) can arise from numerous genetic defects. To date, variants in the EXOSC gene family have been associated with such disorders. Using next-generation sequencing (NGS), known and novel variants in this gene family causing autosomal recessive ID (ARID) have been identified in five Iranian families. By collecting clinical information on these families and comparing their phenotypes with previously reported patients, we further describe the clinical variability of ARID resulting from alterations in the EXOSC gene family, and emphasize the role of RNA processing dysregulation in ARID.
Assuntos
Complexo Multienzimático de Ribonucleases do Exossomo/genética , Genes Recessivos , Deficiência Intelectual/genética , Criança , Pré-Escolar , Estudos de Coortes , Consanguinidade , Família , Feminino , Humanos , Lactente , Deficiência Intelectual/patologia , Deficiência Intelectual/fisiopatologia , Irã (Geográfico) , Masculino , Mutação , Linhagem , Sequenciamento do ExomaRESUMO
Pyroptosis can be triggered through both canonical and non-canonical inflammasome pathways, involving the cleavage of gasdermin (GSDM) protein family members, like GSDMD and GSDME. The impact of pyroptosis on tumors is nuanced, because its role in regulating cancer progression and anti-tumor immunity may vary depending on the tumor type, stage, location, and immune status. However, pyroptosis cannot be simply categorized as promoting or inhibiting tumors based solely on whether it is acute or chronic in nature. The interplay between pyroptosis and cancer is intricate, with some evidence suggesting that chronic pyroptosis may facilitate tumor growth, while the acute induction of pyroptosis could stimulate anti-cancer immune responses. Tumor hypoxia activates hypoxia inducible factor (HIF) signaling to modulate pyroptosis and immune checkpoint expression. Targeting this hypoxia-pyroptosis-immune escape axis could be a promising therapeutic strategy. This review highlights the complex crosstalk between hypoxia, pyroptosis, and immune evasion in the TME.
Assuntos
Neoplasias , Piroptose , Evasão Tumoral , Humanos , Piroptose/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/patologia , Neoplasias/metabolismo , Animais , Microambiente Tumoral/imunologia , Transdução de Sinais , Hipóxia/imunologia , Hipóxia/metabolismoRESUMO
Next-generation sequencing (NGS) has been proven to be one of the most powerful diagnostic tools for rare Mendelian disorders. Several studies on the clinical application of NGS in unselected cohorts of Middle Eastern patients have reported a high diagnostic yield of up to 48%, correlated with a high level of consanguinity in these populations. We evaluated the diagnostic utility of NGS-based testing across different clinical indications in 1436 patients from Iran, representing the first study of its kind in this highly consanguineous population. A total of 1075 exome sequencing and 361 targeted gene panel sequencing were performed over 8 years at a single clinical genetics laboratory, with the majority of cases tested as proband-only (91.6%). The overall diagnostic rate was 46.7%, ranging from 24% in patients with an abnormality of prenatal development to over 67% in patients with an abnormality of the skin. We identified 660 pathogenic or likely pathogenic variants, including 241 novel variants, associated with over 342 known genetic conditions. The highly consanguineous nature of this cohort led to the diagnosis of autosomal recessive disorders in the majority of patients (79.1%) and allowed us to determine the shared carrier status of couples for suspected recessive phenotypes in their deceased child(ren) when direct testing was not possible. We also highlight the observations of recessive inheritance of genes previously associated only with dominant disorders and provide an expanded genotype-phenotype spectrum for multiple less-characterized genes. We present the largest mutational spectrum of known Mendelian disease, including possible founder variants, throughout the Iranian population, which can serve as a unique resource for clinical genomic studies locally and beyond.
RESUMO
The seizure threshold 2 (SZT2) gene has been shown to confer a low seizure threshold and may enhance epileptogenesis in mice. However, its biological function is still not known. Mutations in SZT2 have been reported in very few patients and features range from mild to moderate intellectual disability without seizures to severe intellectual disability with epileptic encephalopathies with severe developmental delay. Here, we report a six-year-old boy with a novel homozygous mutation in SZT2 gene with intellectual disability, seizures, absent speech and autistic features. We are reporting the first patient with autistic features including very little or no eye contact, arm flapping and repetitive behaviour.
Assuntos
Transtorno Autístico/genética , Deficiência Intelectual/genética , Proteínas do Tecido Nervoso/genética , Convulsões/genética , Transtorno Autístico/patologia , Criança , Homozigoto , Humanos , Deficiência Intelectual/patologia , Masculino , Mutação , Convulsões/patologiaRESUMO
BACKGROUND: Diagnosis of hereditary hearing loss (HHL) as a heterogeneous disorder is very important especially in countries with high rates of consanguinity where the autosomal recessive pattern of inheritance is prevalent. Techniques such as next-generation sequencing, a comprehensive genetic test using targeted genomic enrichment and massively parallel sequencing (TGE + MPS), have made the diagnosis more cost-effective. The aim of this study was to determine HHL variants with comprehensive genetic testing in our country. METHODS: Fifty GJB2 negative individuals with HHL were referred to the Kariminejad-Najmabadi Pathology and Genetics Center, Tehran, one of the reference diagnostic genetic laboratories in Iran, during a 3-year period between 2014 and 2017. They were screened with the OtoSCOPE test, the targeted genomic enrichment and massively parallel sequencing (TGE + MPS) platform after a detailed history had been taken along with clinical evaluation. RESULTS: Among 32 out of 50 GJB2 negative patients (64%), 34 known pathogenic and novel variants were detected of which 16 (47%) were novel, identified in 10 genes of which the most prevalent were CDH23, MYO7A and MYO15A. CONCLUSION: These results provide a foundation from which to make appropriate recommendations for the use of comprehensive genetic testing in the evaluation of Iranian patients with hereditary hearing loss.
RESUMO
The calcium channel, voltage-dependent, L-type, alpha 1S subunit (CACNA1S) gene encodes a skeletal Ca2+ channel which is involved in calcium-dependent processes such as muscle contraction and neurotransmitter release. Mutations in this gene have been accompanied by hypo- and normokalemic periodic paralysis, thyrotoxic periodic paralysis, and susceptibility to malignant hyperthermia. We report the clinical and genetic findings in a patient diagnosed with metabolic myopathy who had episodic attacks of muscle pain and weakness but with no family background of the disease. Next-generation sequencing (NGS) using a panel targeting metabolic myopathy and myotonia genes identified a de novo heterozygous pathogenic variant c.3724A>G, p.Arg1242Gly, in exon 30 of CACNA1S. As the second report of this variant, this case may broaden the CACNA1S-related disease spectrum to include normokalemic periodic paralysis.