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1.
J Clin Immunol ; 44(4): 93, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578360

RESUMO

Newborn screening (NBS) for severe inborn errors of immunity (IEI), affecting T lymphocytes, and implementing measurements of T cell receptor excision circles (TREC) has been shown to be effective in early diagnosis and improved prognosis of patients with these genetic disorders. Few studies conducted on smaller groups of newborns report results of NBS that also include measurement of kappa-deleting recombination excision circles (KREC) for IEI affecting B lymphocytes. A pilot NBS study utilizing TREC/KREC detection was conducted on 202,908 infants born in 8 regions of Russia over a 14-month period. One hundred thirty-four newborns (0.66‰) were NBS positive after the first test and subsequent retest, 41% of whom were born preterm. After lymphocyte subsets were assessed via flow cytometry, samples of 18 infants (0.09‰) were sent for whole exome sequencing. Confirmed genetic defects were consistent with autosomal recessive agammaglobulinemia in 1/18, severe combined immunodeficiency - in 7/18, 22q11.2DS syndrome - in 4/18, combined immunodeficiency - in 1/18 and trisomy 21 syndrome - in 1/18. Two patients in whom no genetic defect was found met criteria of (severe) combined immunodeficiency with syndromic features. Three patients appeared to have transient lymphopenia. Our findings demonstrate the value of implementing combined TREC/KREC NBS screening and inform the development of policies and guidelines for its integration into routine newborn screening programs.


Assuntos
Linfopenia , Imunodeficiência Combinada Severa , Lactente , Recém-Nascido , Humanos , Triagem Neonatal/métodos , Projetos Piloto , Linfopenia/diagnóstico , Linfócitos T , Imunodeficiência Combinada Severa/diagnóstico , Imunodeficiência Combinada Severa/genética , DNA , Receptores de Antígenos de Linfócitos T/genética
2.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731816

RESUMO

This study, conducted in the Republic of North Ossetia-Alania (RNOA), aimed to explore the genetic landscape of hyperphenylalaninemia (HPA) and phenylketonuria (PKU) in the Ossetian population using data from newborn screening (NBS). Through comprehensive molecular genetic analysis of 29 patients with HPA from diverse ethnic backgrounds, two major genetic variants in the PAH gene, P281L and P211T, were identified, constituting 50% of all detected pathogenic alleles in Ossetian patients. Remarkably, these variants exhibited an exceptionally high frequency in the Ossetian population, surpassing global prevalence rates. This study unveiled a notable prevalence of mild forms of HPA (78%), underscoring the importance of genetic counseling for carriers of pathogenic variants in the PAH gene. Moreover, the findings emphasized the necessity for ongoing monitoring of patients with mild forms, as they may lack significant symptoms for diagnosis, potentially impacting offspring. Overall, this research offers valuable insights into the genetic landscape of HPA and PKU in the Ossetian population.


Assuntos
Fenilalanina Hidroxilase , Fenilcetonúrias , Humanos , Fenilcetonúrias/genética , Fenilcetonúrias/epidemiologia , Feminino , Fenilalanina Hidroxilase/genética , Masculino , Recém-Nascido , Triagem Neonatal , Alelos , Frequência do Gene
3.
Curr Issues Mol Biol ; 46(1): 96-105, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38248310

RESUMO

This study investigates a unique and complex eye phenotype characterized by minimal iris defects, foveal hypoplasia, optic nerve coloboma, and severe posterior segment damage. Through genetic analysis and bioinformatic tools, a specific nonsynonymous substitution, p.(Asn114Ser), within the PAX6 gene's paired domain is identified. Although this substitution is not in direct contact with DNA, its predicted stabilizing effect on the protein structure challenges the traditional understanding of PAX6 mutations, suggesting a gain-of-function mechanism. Contrary to classical loss-of-function effects, this gain-of-function hypothesis aligns with research demonstrating PAX6's dosage sensitivity. Gain-of-function mutations, though less common, can lead to diverse phenotypes distinct from aniridia. Our findings emphasize PAX6's multifaceted influence on ocular phenotypes and the importance of genetic variations. We contribute a new perspective on PAX6 mutations by suggesting a potential gain-of-function mechanism and showcasing the complexities of ocular development. This study sheds light on the intricate interplay of the genetic alterations and regulatory mechanisms underlying complex eye phenotypes. Further research, validation, and collaboration are crucial to unravel the nuanced interactions shaping ocular health and development.

4.
Am J Hum Genet ; 107(2): 234-250, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32668217

RESUMO

Phenylketonuria (PKU), caused by variants in the phenylalanine hydroxylase (PAH) gene, is the most common autosomal-recessive Mendelian phenotype of amino acid metabolism. We estimated that globally 0.45 million individuals have PKU, with global prevalence 1:23,930 live births (range 1:4,500 [Italy]-1:125,000 [Japan]). Comparing genotypes and metabolic phenotypes from 16,092 affected subjects revealed differences in disease severity in 51 countries from 17 world regions, with the global phenotype distribution of 62% classic PKU, 22% mild PKU, and 16% mild hyperphenylalaninemia. A gradient in genotype and phenotype distribution exists across Europe, from classic PKU in the east to mild PKU in the southwest and mild hyperphenylalaninemia in the south. The c.1241A>G (p.Tyr414Cys)-associated genotype can be traced from Northern to Western Europe, from Sweden via Norway, to Denmark, to the Netherlands. The frequency of classic PKU increases from Europe (56%) via Middle East (71%) to Australia (80%). Of 758 PAH variants, c.1222C>T (p.Arg408Trp) (22.2%), c.1066-11G>A (IVS10-11G>A) (6.4%), and c.782G>A (p.Arg261Gln) (5.5%) were most common and responsible for two prevalent genotypes: p.[Arg408Trp];[Arg408Trp] (11.4%) and c.[1066-11G>A];[1066-11G>A] (2.6%). Most genotypes (73%) were compound heterozygous, 27% were homozygous, and 55% of 3,659 different genotypes occurred in only a single individual. PAH variants were scored using an allelic phenotype value and correlated with pre-treatment blood phenylalanine concentrations (n = 6,115) and tetrahydrobiopterin loading test results (n = 4,381), enabling prediction of both a genotype-based phenotype (88%) and tetrahydrobiopterin responsiveness (83%). This study shows that large genotype databases enable accurate phenotype prediction, allowing appropriate targeting of therapies to optimize clinical outcome.


Assuntos
Predisposição Genética para Doença/genética , Fenilcetonúrias/epidemiologia , Fenilcetonúrias/genética , Alelos , Biopterinas/análogos & derivados , Biopterinas/genética , Europa (Continente) , Frequência do Gene/genética , Estudos de Associação Genética/métodos , Genótipo , Homozigoto , Humanos , Mutação/genética , Fenótipo , Fenilalanina/sangue , Fenilalanina Hidroxilase/genética , Fenilcetonúrias/sangue
5.
Int J Mol Sci ; 24(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37958513

RESUMO

This study aims to present a clinical case involving the unique co-occurrence of congenital aniridia and Down syndrome in a young girl and to analyze the combined impact of these conditions on the patient's phenotype. The investigation involved comprehensive pediatric and ophthalmological examinations alongside karyotyping and Sanger sequencing of the PAX6 gene. The patient exhibited distinctive features associated with both congenital aniridia and Down syndrome, suggesting a potential exacerbation of their effects. Cytogenetic and molecular genetic analysis revealed the presence of trisomy 21 and a known pathogenic nonsense variant in exon 6 of the PAX6 gene (c.282C>A, p.(Cys94*)) corresponding to the paired domain of the protein. The observation of these two hereditary anomalies offers valuable insights into the molecular pathogenetic mechanisms underlying each condition. Additionally, it provides a basis for a more nuanced prognosis of the complex disease course in this patient. This case underscores the importance of considering interactions between different genetic disorders in clinical assessments and treatment planning.


Assuntos
Aniridia , Síndrome de Down , Feminino , Humanos , Criança , Síndrome de Down/complicações , Fator de Transcrição PAX6/genética , Cromossomos Humanos Par 21/genética , Trissomia , Aniridia/complicações , Aniridia/genética , Proteínas do Olho/genética , Proteínas de Homeodomínio/genética , Linhagem , Mutação
6.
Int J Mol Sci ; 24(22)2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-38003421

RESUMO

Inherited retinal diseases (IRDs) constitute a prevalent group of inherited ocular disorders characterized by marked genetic diversity alongside moderate clinical variability. Among these, ABCA4-related eye pathology stands as a prominent form affecting the retina. In this study, we conducted an in-depth analysis of 96 patients harboring ABCA4 variants in the European part of Russia. Notably, the complex allele c.[1622T>C;3113C>T] (p.Leu541Pro;Ala1038Val, or L541P;A1038V) and the variant c.5882G>A (p.Gly1961Glu or G1961E) emerged as primary contributors to this ocular pathology within this population. Additionally, we elucidated distinct disease progression characteristics associated with the G1961E variant. Furthermore, our investigation revealed that patients with loss-of-function variants in ABCA4 were more inclined to develop phenotypes distinct from Stargardt disease. These findings provide crucial insights into the genetic and clinical landscape of ABCA4-related retinal dystrophies in this specific population.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Distrofias Retinianas , Humanos , Mutação , Alelos , Transportadores de Cassetes de Ligação de ATP/genética , Distrofias Retinianas/genética , Distrofias Retinianas/patologia , Fenótipo
7.
Int J Mol Sci ; 24(14)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37511043

RESUMO

The fragment of satellite III (f-SatIII) is located in pericentromeric heterochromatin of chromosome 1. Cell with an enlarged f-SatIII block does not respond to various stimuli and are highly stress-susceptible. The fraction of f-SatIII in the cells of schizophrenia patients changed during antipsychotic therapy. Therefore, antipsychotics might reduce the f-SatIII content in the cells. We studied the action of haloperidol, risperidone and olanzapine (3 h, 24 h, 96 h) on human skin fibroblast lines (n = 10). The f-SatIII contents in DNA were measured using nonradioactive quantitative hybridization. RNASATIII were quantified using RT-qPCR. The levels of DNA damage markers (8-oxodG, γ-H2AX) and proteins that regulate apoptosis and autophagy were determined by flow cytometry. The antipsychotics reduced the f-SatIII content in DNA and RNASATIII content in RNA from HSFs. After an exposure to the antipsychotics, the autophagy marker LC3 significantly increased, while the apoptosis markers decreased. The f-SatIII content in DNA positively correlated with RNASATIII content in RNA and with DNA oxidation marker 8-oxodG, while negatively correlated with LC3 content. The antipsychotics arrest the process of f-SatIII repeat augmentation in cultured skin fibroblasts via the transcription suppression and/or through upregulated elimination of cells with enlarged f-SatIII blocks with the help of autophagy.


Assuntos
Antipsicóticos , Humanos , Antipsicóticos/farmacologia , Variações do Número de Cópias de DNA , 8-Hidroxi-2'-Desoxiguanosina , DNA , RNA , Benzodiazepinas
8.
Int J Mol Sci ; 24(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36901946

RESUMO

North Caucasus has always been a residence of a lot of different authentic ethnic groups speaking different languages and still living their traditional lifestyle. The diversity appeared to be reflected in the accumulation of different mutations causing common inherited disorders. X-linked ichthyosis represents the second most common form of genodermatoses after ichthyosis vulgaris. Eight patients from three unrelated families of different ethnic origin, Kumyk, Turkish Meskhetians, and Ossetian, with X-linked ichthyosis from the North Caucasian Republic of North Ossetia-Alania were examined. NGS technology was implied for searching for disease-causing variants in one of the index patients. Known pathogenic hemizygous deletion in the short arm of chromosome X encompassing the STS gene was defined in the Kumyk family. A further analysis allowed us to establish that likely the same deletion was a cause of ichthyosis in a family belonging to the Turkish Meskhetians ethnic group. In the Ossetian family, a likely pathogenic nucleotide substitution in the STS gene was defined; it segregated with the disease in the family. We molecularly confirmed XLI in eight patients from three examined families. Though in two families, Kumyk and Turkish Meskhetian, we revealed similar hemizygous deletions in the short arm of chromosome X, but their common origin was not likely. Forensic STR markers of the alleles carrying the deletion were defined to be different. However, here, common alleles haplotype is hard to track for a high local recombination rate. We supposed the deletion could arise as a de novo event in a recombination hot spot in the described and in other populations with a recurrent character. Defined here are the different molecular genetic causes of X-linked ichthyosis in families of different ethnic origins sharing the same residence place in the Republic of North Ossetia-Alania which could point to the existing reproductive barriers even inside close neighborhoods.


Assuntos
Ictiose Ligada ao Cromossomo X , Ictiose , Humanos , Esteril-Sulfatase/genética , Heterogeneidade Genética , Ictiose Ligada ao Cromossomo X/genética , Ictiose/genética , Cromossomo X
9.
Int J Mol Sci ; 24(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38069245

RESUMO

Three years ago, our patient, at that time a 16-month-old boy, was discovered to have bilateral kidney lesions with a giant tumor in the right kidney. Chemotherapy and bilateral nephron-sparing surgery (NSS) for Wilms tumor with nephroblastomatosis was carried out. The patient also had eye affection, including glaucoma, eye enlargement, megalocornea, severe corneal swelling and opacity, complete aniridia, and nystagmus. The diagnosis of WAGR syndrome was suspected. De novo complex chromosomal rearrangement with balanced translocation t(10,11)(p15;p13) and a pericentric inversion inv(11)(p13q12), accompanied by two adjacent 11p14.1p13 and 11p13p12 deletions, were identified. Deletions are raised through the complex molecular mechanism of two subsequent rearrangements affecting chromosomes 11 and 10. WAGR syndrome diagnosis was clinically and molecularly confirmed, highlighting the necessity of comprehensive genetic testing in patients with congenital aniridia and/or WAGR syndrome.


Assuntos
Aniridia , Neoplasias Renais , Síndrome WAGR , Tumor de Wilms , Masculino , Humanos , Lactente , Síndrome WAGR/diagnóstico , Síndrome WAGR/genética , Síndrome WAGR/patologia , Deleção Cromossômica , Aniridia/diagnóstico , Aniridia/genética , Tumor de Wilms/genética , Neoplasias Renais/genética , Cromossomos Humanos Par 11/genética , Inversão Cromossômica
10.
Int J Mol Sci ; 24(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37569717

RESUMO

Traumatic brain injuries account for 30-50% of all physical traumas and are the most common pathological diseases of the brain. Mechanical damage of brain tissue leads to the disruption of the blood-brain barrier and the massive death of neuronal, glial, and endothelial cells. These events trigger a neuroinflammatory response and neurodegenerative processes locally and in distant parts of the brain and promote cognitive impairment. Effective instruments to restore neural tissue in traumatic brain injury are lacking. Glial cells are the main auxiliary cells of the nervous system, supporting homeostasis and ensuring the protection of neurons through contact and paracrine mechanisms. The glial cells' secretome may be considered as a means to support the regeneration of nervous tissue. Consequently, this study focused on the therapeutic efficiency of composite proteins with a molecular weight of 5-100 kDa secreted by glial progenitor cells in a rat model of traumatic brain injury. The characterization of proteins below 100 kDa secreted by glial progenitor cells was evaluated by proteomic analysis. Therapeutic effects were assessed by neurological outcomes, measurement of the damage volume by MRI, and an evaluation of the neurodegenerative, apoptotic, and inflammation markers in different areas of the brain. Intranasal infusions of the composite protein product facilitated the functional recovery of the experimental animals by decreasing the inflammation and apoptotic processes, preventing neurodegenerative processes by reducing the amounts of phosphorylated Tau isoforms Ser396 and Thr205. Consistently, our findings support the further consideration of glial secretomes for clinical use in TBI, notably in such aspects as dose-dependent effects and standardization.


Assuntos
Lesões Encefálicas Traumáticas , Células Endoteliais , Ratos , Animais , Ratos Sprague-Dawley , Células Endoteliais/metabolismo , Proteômica , Lesões Encefálicas Traumáticas/metabolismo , Neuroglia/metabolismo , Inflamação , Células-Tronco/metabolismo
11.
Int J Mol Sci ; 24(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38139172

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive molecular subtype, with a poor survival rate compared to others subtypes. For a long time, chemotherapy was the only systemic treatment for TNBC, and the identification of actionable molecular targets might ultimately improve the prognosis for TNBC patients. We performed a genome-wide analysis of DNA methylation at CpG islands on a collection of one hundred ten breast carcinoma samples and six normal breast tissue samples using reduced representation bisulfite sequencing with the XmaI restriction enzyme (XmaI-RRBS) and identified a subset of TNBC samples with significant hypomethylation at the LTB4R/LTB4R2 genes' CpG islands, including CpG dinucleotides covered with cg12853742 and cg21886367 HumanMethylation 450K microarray probes. Abnormal DNA hypomethylation of this region in TNBC compared to normal samples was confirmed by bisulfite Sanger sequencing. Gene expression generally anticorrelates with promoter methylation, and thus, the promoter hypomethylation detected and confirmed in our study might be revealed as an indirect marker of high LTB4R/LTB4R2 expression using a simple methylation-sensitive PCR test. Analysis of RNA-seq expression and DNA methylation data from the TCGA dataset demonstrates that the expression of the LTB4R and LTB4R2 genes significantly negatively correlates with DNA methylation at both CpG sites cg12853742 (R = -0.4, p = 2.6 × 10-6; R = -0.21, p = 0.015) and cg21886367 (R = -0.45, p = 7.3 × 10-8; R = -0.24, p = 0.005), suggesting the upregulation of these genes in tumors with abnormal hypomethylation of their CpG island. Kaplan-Meier analysis using the TCGA-BRCA gene expression and clinical data revealed poorer overall survival for TNBC patients with an upregulated LTB4R. To this day, only the leukotriene inhibitor LY255283 has been tested on an MCF-7/DOX cell line, which is a luminal A breast cancer molecular subtype. Other studies compare the effects of Montelukast and Zafirlukast (inhibitors of the cysteinyl leukotriene receptor, which is different from LTB4R/LTB4R2) on the MDA-MB-231 (TNBC) cell line, with high methylation and low expression levels of LTB4R. In our study, we assess the therapeutic effects of various drugs (including leukotriene receptor inhibitors) with the DepMap gene effect and drug sensitivity data for TNBC cell lines with hypomethylated and upregulated LTB4R/LTB4R2 genes. LY255283, Minocycline, Silibinin, Piceatannol, Mitiglinide, 1-Azakenpaullone, Carbetocin, and Pim-1-inhibitor-2 can be considered as candidates for the additional treatment of TNBC patients with tumors demonstrating LTB4R/LTB4R2 hypomethylation/upregulation. Finally, our results suggest that the epigenetic status of leukotriene B4 receptors is a novel, potential, predictive, and prognostic biomarker for TNBC. These findings might improve individualized therapy for TNBC patients by introducing new therapeutic adjuncts as anticancer agents.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Epigenômica , Receptores de Leucotrienos
12.
BMC Genomics ; 23(1): 252, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365085

RESUMO

Cystic fibrosis (CF, MIM# 219,700) is an autosomal recessive disease caused by pathogenic variants within the CFTR gene. It was shown that genetic variants located in cis can affect disease severity or treatment response because of additive or epistatic effects. Studies on the prevalence of complex alleles in Russian CF patients have just begun. Aim To evaluate frequencies and genetic background of complex alleles carrying c.1521_1523delCTT (F508del) and c.1399C>T (L467F), c.2562T>G (T854=) or c.4389G>A (Q1463=) in cis; to determine clinical consequences of complex allele c.[1399C>T;1521_1523delCTT] ([L467;F508del]) in Russian CF patients. Methods Sequencing of coding regions of CFTR gene and analysis of polymorphic markers in CF patients carrying F508del variant. Comparing of clinical features in two groups patients having genotypes [L467F;F508del];[F508del] (group 1) and [F508del];[F508del] (group 2). Results Frequency of [L467F;F508del] allele linked to 2-2-21-6-17-13 haplotype was 4.42%, of [F508del;T854=;Q1463=] allele linked to haplotype 1-2-21-6-17-13 - 2.2% in F508del chromosomes. No differences in disease severity in patients carrying complex allele [L467F;F508del] and patients homozygous for F508del was found. Conclusion The frequency of complex alleles associated with F508del was at least 6.6% in Russian CF patients, which should be taken into account for the decision on optimal treatment options with CFTR modulators.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Peptídeos Cíclicos/metabolismo , Alelos , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Haplótipos , Homozigoto , Humanos
13.
J Med Genet ; 58(4): 270-274, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32467297

RESUMO

BackgroundAniridia is a severe autosomal dominant panocular disorder associated with pathogenic sequence variants of the PAX6 gene or 11p13 chromosomal aberrations encompassing the coding and/or regulatory regions of the PAX6 gene in a heterozygous state. Patients with aniridia display several ocular anomalies including foveal hypoplasia, cataract, keratopathy, and glaucoma, which can vary in severity and combination.MethodsA cohort of 155 patients from 125 unrelated families with identified point PAX6 pathogenic variants (118 patients) or large chromosomal 11p13 deletions (37 patients) was analyzed. Genetic causes were divided into 6 types. The occurrence of 6 aniridic eye anomalies was analyzed. Fisher's exact test was applied for 2×2 contingency tables assigning numbers of patients with/without each sign and each type of the PAX6 variants or 11p13 deletions with Benjamini-Hochberg correction. The age of patients with different types of mutation did not differ.ResultsPatients with 3'-cis-regulatory region deletions had a milder aniridia phenotype without keratopathy, nystagmus, or foveal hypoplasia. The phenotypes of the patients with other rearrangements involving 11p13 do not significantly differ from those associated with point pathogenic variants in the PAX6 gene. Missense mutations and genetic variants disrupting splicing are associated with a severe aniridia phenotype and resemble loss-of-function mutations. It is particularly important that in all examined patients, PAX6 mutations were found to be associated with multiple eye malformations. The age of patients with keratopathy, cataract, and glaucoma was significantly higher than the age of patients without these signs.ConclusionWe got clear statistically significant genotype-phenotype correlations in congenital aniridia and evident that aniridia severity indeed had worsened with age.


Assuntos
Aniridia/genética , Anormalidades do Olho/genética , Predisposição Genética para Doença , Fator de Transcrição PAX6/genética , Adolescente , Adulto , Aniridia/epidemiologia , Aniridia/patologia , Catarata/epidemiologia , Catarata/genética , Criança , Pré-Escolar , Anormalidades do Olho/epidemiologia , Anormalidades do Olho/patologia , Feminino , Estudos de Associação Genética , Glaucoma/epidemiologia , Glaucoma/genética , Humanos , Masculino , Mutação de Sentido Incorreto/genética , Linhagem , Adulto Jovem
14.
Int J Mol Sci ; 23(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35743132

RESUMO

Genome-wide sequencing metadata allows researchers to infer bias in the relative frequencies of mutational events and to predict putative mutagenic models. In addition, much less data could be useful in the evaluation of the mutational frequency spectrum and the prevalent local mutagenic process. Here we analyzed the PAX6 gene locus for mutational spectra obtained in our own and previous studies and compared them with data on other genes as well as the whole human genome. MLPA and Sanger sequencing were used for mutation searching in a cohort of 199 index patients from Russia with aniridia and aniridia-related phenotypes. The relative frequencies of different categories of PAX6 mutations were consistent with those previously reported by other researchers. The ratio between substitutions, small indels, and chromosome deletions in the 11p13 locus was within the interval previously published for 20 disease associated genomic loci, but corresponded to a higher end due to very high frequencies of small indels and chromosome deletions. The ratio between substitutions, small indels, and chromosome deletions for disease associated genes, including the PAX6 gene as well as the share of PAX6 missense mutations, differed considerably from those typical for the whole genome.


Assuntos
Aniridia , Fatores de Transcrição Box Pareados , Aniridia/genética , Deleção Cromossômica , Proteínas do Olho/genética , Genoma Humano , Proteínas de Homeodomínio/genética , Humanos , Mutação , Fator de Transcrição PAX6/genética , Fatores de Transcrição Box Pareados/genética , Linhagem , Proteínas Repressoras/genética
15.
Int J Mol Sci ; 23(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36292982

RESUMO

Here, we described three affected boys from two unrelated families of Ossetian-Digor origin from the Republic of North Ossetia-Alania who were admitted to the Research Centre for Medical Genetics with unspecified muscular dystrophy. High-throughput sequencing was performed and revealed two novel frameshift variants in the COL6A2 gene (NM_001849.3) in a heterozygous state each in both cases: c.508_535delinsCTGTGG and c.1659_1660del (case 1) and c.1689del and c.1659_1660del (case 2). In two cases, the same nucleotide variant in the COL6A2 gene (c.1659_1660del) was observed. We have suggested that the variant c.1659_1660del may be common in the Ossetian-Digor population because two analyzed families have the same ancestry from the same subethnic group of Ossetians). The screening for an asymptomatic carriage of the nucleotide variant c.1659_1660del in 54 healthy donors from Ossetian-Digor population revealed that the estimated carrier frequency is 0.0093 (CI: 0.0002-0.0505), which is high for healthy carriers of the pathogenic variant. Molecular genetic, anamnestic data and clinical examination results allowed us to diagnose Ullrich muscular dystrophy in those affected boys. Genetic heterogeneity and phenotypic diversity of muscular dystrophies complicate diagnosis. It is important to make a differential diagnosis of such conditions and use HTS methods to determine the most accurate diagnosis.


Assuntos
Distrofias Musculares , Masculino , Humanos , Distrofias Musculares/genética , Sequenciamento de Nucleotídeos em Larga Escala , Nucleotídeos , Mutação , Colágeno Tipo VI/genética
16.
Hum Mol Genet ; 28(19): 3323-3326, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31304537

RESUMO

WAGR syndrome (OMIM #194072) is a rare genetic disorder that consists of development of Wilms' tumor (nephroblastoma), aniridia, genitourinary anomalies and intellectual disability (mental retardation). It is associated with WAGR-region deletions in the 11p13 chromosome region. Our previous study of congenital aniridia patients revealed a noticeable number of aniridia patients with WAGR-region deletions but without Wilms' tumor in their medical history. We assessed the involvement of other neighboring genes from affected chromosome regions in the patients with and without Wilms' tumor. Reliable confidence was obtained for the LMO2 gene, which is significantly more often deleted in patients with nephroblastoma. Thus, our study presents genetic evidence that the development of Wilms tumors in WAGR syndrome patients should be attributed to the deletion of WT1 and LMO2 rather than WT1 only.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Deleção de Genes , Proteínas com Domínio LIM/genética , Proteínas Proto-Oncogênicas/genética , Síndrome WAGR/genética , Proteínas WT1/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Haploinsuficiência , Humanos , Lactente , Masculino , Prognóstico , Adulto Jovem
17.
Int J Mol Sci ; 23(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35008689

RESUMO

The concept of hormesis describes a phenomenon of adaptive response to low-dose ionizing radiation (LDIR). Similarly, the concept of mitohormesis states that the adaptive program in mitochondria is activated in response to minor stress effects. The mechanisms of hormesis effects are not clear, but it is assumed that they can be mediated by reactive oxygen species. Here, we studied effects of LDIR on mitochondria in mesenchymal stem cells. We have found that X-ray radiation at a dose of 10 cGy as well as oxidized fragments of cell-free DNA (cfDNA) at a concentration of 50 ng/mL resulted in an increased expression of a large number of genes regulating the function of the mitochondrial respiratory chain complexes in human mesenchymal stem cells (MSC). Several genes remained upregulated within hours after the exposure. Both X-ray radiation and oxidized cfDNA resulted in upregulation of FIS1 and MFN1 genes, which regulated fusion and fission of mitochondria, within 3-24 h after the exposure. Three hours after the exposure, the number of copies of mitochondrial DNA in cells had increased. These findings support the hypothesis that assumes oxidized cell-free DNA as a mediator of MSC response to low doses of radiation.


Assuntos
Regulação da Expressão Gênica/efeitos da radiação , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos da radiação , Mitocôndrias/genética , Mitocôndrias/efeitos da radiação , Radiação Ionizante , Ácidos Nucleicos Livres/metabolismo , DNA Mitocondrial/genética , Relação Dose-Resposta à Radiação , Transporte de Elétrons , Dosagem de Genes , Genes Mitocondriais , Humanos , Potencial da Membrana Mitocondrial , Dinâmica Mitocondrial , Oxirredução/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Transcrição Gênica , Raios X
18.
Int J Mol Sci ; 22(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502190

RESUMO

Inductors of myogenic stem cell differentiation attract attention, as they can be used to treat myodystrophies and post-traumatic injuries. Functionalization of fullerenes makes it possible to obtain water-soluble derivatives with targeted biochemical activity. This study examined the effects of the phosphonate C60 fullerene derivatives on the expression of myogenic transcription factors and myogenic differentiation of human mesenchymal stem cells (MSCs). Uptake of the phosphonate C60 fullerene derivatives in human MSCs, intracellular ROS visualization, superoxide scavenging potential, and the expression of myogenic, adipogenic, and osteogenic differentiation genes were studied. The prolonged MSC incubation (within 7-14 days) with the C60 pentaphoshonate potassium salt promoted their differentiation towards the myogenic lineage. The transcription factors and gene expressions determining myogenic differentiation (MYOD1, MYOG, MYF5, and MRF4) increased, while the expression of osteogenic differentiation factors (BMP2, BMP4, RUNX2, SPP1, and OCN) and adipogenic differentiation factors (CEBPB, LPL, and AP2 (FABP4)) was reduced or did not change. The stimulation of autophagy may be one of the factors contributing to the increased expression of myogenic differentiation genes in MSCs. Autophagy may be caused by intracellular alkalosis and/or short-term intracellular oxidative stress.


Assuntos
Fulerenos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Desenvolvimento Muscular , Autofagia , Diferenciação Celular , Células Cultivadas , Regulação da Expressão Gênica , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Proteína MyoD/genética , Fator Regulador Miogênico 5/genética , Miogenina/genética , Espécies Reativas de Oxigênio/metabolismo
19.
J Neuroinflammation ; 17(1): 212, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32677958

RESUMO

BACKGROUND: Autism spectrum disorders (ASD) are known to be associated with an inflammatory process related to immune system dysfunction. This study's aim was to investigate the role of cell-free DNA in chronic inflammatory process in ASD patients. METHODS: The study included 133 ASD patients and 27 healthy controls. Sixty-two ASD patients were demonstrated to have mild-to-moderate disease severity (group I) and 71 individuals to have severe ASD (group II). Plasma cell-free (cf) DNA characteristics, plasma cytokine concentrations, expression of the genes for NFкB1 transcription factor and pro-inflammatory cytokines TNFα, IL-1ß and IL-8 in peripheral blood lymphocytes (PBL) of ASD patients, and unaffected controls were investigated. Additionally, in vitro experiments with oxidized DNA supplementation to PBL cultures derived from ASD patients and healthy controls were performed. RESULTS: The data indicates that ASD patients have demonstrated increased cfDNA concentration in their circulation. cfDNA of patients with severe ASD has been characterized by a high abundance of oxidative modification. Furthermore, ASD patients of both groups have shown elevated plasma cytokine (IL-1ß, IL-8, IL-17A) levels and heightened expression of genes for NFкB1 nuclear factor and pro-inflammatory cytokines TNFα, IL-1ß, and IL-8 in PBL. In vitro experiments have shown that NF-κB/cytokine mRNA expression profiles of ASD patient PBL treated with oxidized DNA fragments were significantly different from those of healthy controls. CONCLUSIONS: It may be proposed that oxidized cfDNA plays a role of stress-signaling factor activating the chronic inflammatory process in patients with ASD.


Assuntos
Transtorno do Espectro Autista/sangue , Ácidos Nucleicos Livres/sangue , Mediadores da Inflamação/sangue , Estresse Oxidativo/fisiologia , Transtorno do Espectro Autista/imunologia , Biomarcadores/sangue , Ácidos Nucleicos Livres/imunologia , Células Cultivadas , Criança , Pré-Escolar , Fragmentação do DNA , Feminino , Humanos , Inflamação/sangue , Inflamação/imunologia , Mediadores da Inflamação/imunologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Masculino
20.
BMC Med Genet ; 21(Suppl 1): 156, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33092543

RESUMO

BACKGROUND: Hereditary ophthalmic pathology is a genetically heterogeneous group of diseases that occur either as an isolated eye disorder or as a symptom of hereditary syndromes (chromosomal or monogenic). Thus, a diagnostic search in some cases of ophthalmic pathology can be time- and cost-consuming. The most challenging situation can arise when prenatal diagnosis is needed during an ongoing pregnancy. CASE PRESENTATION: A family was referred to the Research Centre for Medical Genetics (RCMG) for childbirth risk prognosis at 7-8 week of gestation because a previous child, a six-year-old boy, has congenital aniridia, glaucoma, retinal detachment, severe psychomotor delay, and lack of speech and has had several ophthalmic surgeries. The affected child had been previously tested for PAX6 mutations and 11p13 copy number variations, which revealed no changes. Considering the lack of pathogenic changes and precise diagnosis for the affected boy, NGS sequencing of clinically relevant genes was performed for the ongoing pregnancy; it revealed a novel hemizygous substitution NM_000266.3(NDP):c.385G > T, p.(Glu129*), in the NDP gene, which is associated with Norrie disease (OMIM #310600). Subsequent Sanger validation of the affected boy and his mother confirmed the identified substitution inherited in X-linked recessive mode. Amniotic fluid testing revealed the fetus was hemizygous for the variant and lead to the decision of the family to interrupt the pregnancy. Complications which developed during the termination of pregnancy required hysterectomy due to medical necessity. CONCLUSIONS: Clinical polymorphism of hereditary ophthalmic pathology can severely complicate establishment of an exact diagnosis and make it time- and cost-consuming. NGS appears to be the method-of-choice in complicated cases, and this could substantially hasten the establishment of a diagnosis and genetic risk estimation.


Assuntos
Cegueira/congênito , Proteínas do Olho/genética , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Proteínas do Tecido Nervoso/genética , Doenças do Sistema Nervoso/diagnóstico , Diagnóstico Pré-Natal/métodos , Degeneração Retiniana/diagnóstico , Espasmos Infantis/diagnóstico , Substituição de Aminoácidos , Cegueira/diagnóstico , Cegueira/genética , Olho/patologia , Feminino , Genes Ligados ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Humanos , Doenças do Sistema Nervoso/genética , Gravidez , Degeneração Retiniana/genética , Espasmos Infantis/genética , Sequenciamento do Exoma
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