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1.
Ann Hum Genet ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39092543

RESUMEN

The primary etiology of congenital hearing loss is attributed to genetic factors, with GJB2 identified as a pivotal gene across diverse ethnic groups. Additionally, nonsyndromic hearing loss is predominantly inherited in an autosomal recessive manner. We used Sanger sequencing to analyze GJB2 in 17 deaf children from 13 unrelated Ivory Coast families. One family had two children born with severe congenital deafness and exhibited pathogenic compound heterozygous variants. These variants included a nonsense substitution (c.132G > A or p.Trp44Ter) and a newly discovered duplication of 7 base pairs (c.205_211dupTTCCCCA or p.Ser72ProfsTer32). Segregation testing confirmed these variants, marking the first identification of GJB2 in an Ivorian family with congenital hearing loss.

2.
Microbiol Resour Announc ; : e0055924, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162483

RESUMEN

In this study, we report the identification of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) JN.1 variant and the quasi-complete genomic sequencing of four clinical samples in Morocco. Nasopharyngeal swabs were obtained from four patients (one female, three males). The Illumina COVIDSeq Test was used for comprehensive genomic analysis.

3.
Mol Biol Rep ; 51(1): 850, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39052101

RESUMEN

BACKGROUND: Syndromic hearing loss (SHL) is characterized by hearing impairment accompanied by other clinical manifestations, reaching over 400 syndromes. Early and accurate diagnosis is essential to understand the progression of hearing loss and associated systemic complications. METHODS AND RESULTS: In this study, we investigated the genetic etiology of sensorineural hearing loss in three Moroccan patients using whole exome sequencing (WES). The results revealed in two families Perrault syndrome caused by LARS2, p. Asn153His; p. Thr629Met compound heterozygous variants in two siblings in one family; and p. Thr522Asn, a homozygous variant in two sisters in another. The patient in the third family was diagnosed with D-bifunctional protein deficiency (D-BPD), linked to compound heterozygous mutations p. Asn457Tyr and p. Val643Argfs*5 in HSD17B4. Molecular dynamic simulation results showed that Val643Argfs*5 does not prevent HSD17B4 protein from binding to the PEX5 receptor, but further studies are recommended to verify its effect on HSD17B4 protein functionality. CONCLUSION: These results highlight the effectiveness of WES in identifying pathogenic mutations involved in heterogeneous disorders and the usefulness of bioinformatics in predicting their effects on protein structure.


Asunto(s)
Aminoacil-ARNt Sintetasas , Disgenesia Gonadal 46 XX , Pérdida Auditiva Sensorineural , Proteína-2 Multifuncional Peroxisomal , Niño , Femenino , Humanos , Masculino , Aminoacil-ARNt Sintetasas/genética , Secuenciación del Exoma , Disgenesia Gonadal 46 XX/genética , Pérdida Auditiva Sensorineural/genética , Marruecos , Mutación/genética , Linaje , Proteína-2 Multifuncional Peroxisomal/genética
4.
Nat Genet ; 56(8): 1556-1565, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38977855

RESUMEN

The African BioGenome Project (AfricaBP) Open Institute for Genomics and Bioinformatics aims to overcome barriers to capacity building through its distributed African regional workshops and prioritizes the exchange of grassroots knowledge and innovation in biodiversity genomics and bioinformatics. In 2023, we implemented 28 workshops on biodiversity genomics and bioinformatics, covering 11 African countries across the 5 African geographical regions. These regional workshops trained 408 African scientists in hands-on molecular biology, genomics and bioinformatics techniques as well as the ethical, legal and social issues associated with acquiring genetic resources. Here, we discuss the implementation of transformative strategies, such as expanding the regional workshop model of AfricaBP to involve multiple countries, institutions and partners, including the proposed creation of an African digital database with sequence information relating to both biodiversity and agriculture. This will ultimately help create a critical mass of skilled genomics and bioinformatics scientists across Africa.


Asunto(s)
Biología Computacional , Genómica , Genómica/educación , Biología Computacional/métodos , Biología Computacional/educación , África , Humanos , Biodiversidad
5.
Bioinformation ; 20(3): 261-270, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38712004

RESUMEN

TYMP gene, which codes for thymidine phosphorylase (TP) is also known as platelet-derived endothelial cell growth factor (PD-ECGF). TP plays crucial roles in nucleotide metabolism and angiogenesis. Mutations in the TYMP gene can lead to Mitochondrial Neurogastrointestinal Encephalopathy (MNGIE) syndrome, a rare genetic disorder. Our main objective was to evaluate the impact of detrimental non-synonymous single nucleotide polymorphisms (nsSNPs) on TP protein structure and predict harmful variants in untranslated regions (UTR). We employed a combination of predictive algorithms to identify nsSNPs with potential deleterious effects, followed by molecular modeling analysis to understand their effects on protein structure and function. Using 13 algorithms, we identified 119 potentially deleterious nsSNPs, with 82 located in highly conserved regions. Of these, 53 nsSNPs were functional and exposed, while 79 nsSNPs reduced TP protein stability. Further analysis of 18 nsSNPs through 3D protein structure analysis revealed alterations in amino acid interactions, indicating their potential impact on protein function. This will help in the development of faster and more efficient genetic tests for detecting TYMP gene mutations.

6.
Transl Oncol ; 44: 101940, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38537326

RESUMEN

Precision Medicine is being increasingly used in the developed world to improve health care. While several Precision Medicine (PM) initiatives have been launched worldwide, their implementations have proven to be more challenging particularly in low- and middle-income countries. To address this issue, the "Personalized Medicine in North Africa" initiative (PerMediNA) was launched in three North African countries namely Tunisia, Algeria and Morocco. PerMediNA is coordinated by Institut Pasteur de Tunis together with the French Ministry for Europe and Foreign Affairs, with the support of Institut Pasteur in France. The project is carried out along with Institut Pasteur d'Algérie and Institut Pasteur du Maroc in collaboration with national and international leading institutions in the field of PM including Institut Gustave Roussy in Paris. PerMediNA aims to assess the readiness level of PM implementation in North Africa, to strengthen PM infrastructure, to provide workforce training, to generate genomic data on North African populations, to implement cost effective, affordable and sustainable genetic testing for cancer patients and to inform policy makers on how to translate research knowledge into health products and services. Gender equity and involvement of young scientists in this implementation process are other key goals of the PerMediNA project. In this paper, we are describing PerMediNA as the first PM implementation initiative in North Africa. Such initiatives contribute significantly in shortening existing health disparities and inequities between developed and developing countries and accelerate access to innovative treatments for global health.

7.
Mol Biol Rep ; 50(12): 10663-10669, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37924449

RESUMEN

OBJECTIVES: The most prevalent sensory disease in humans is deafness. A variety of genes have been linked to hearing loss, which can either be isolated (non-syndromic) or associated with lesions in other organs (syndromic). It has been discovered that WHRN variants are responsible for non-syndromic hearing loss and Usher syndrome type II. METHODS AND RESULTS: Exome sequencing in a consanguineous Moroccan patient with severe hearing loss identified a single homozygous mutation c.619G > T; p.Ala207Ser in WHRN, encoding a cytoskeletal scaffold protein that binds membrane protein complexes to the cytoskeleton in ocular photoreceptors and ear hair cell stereocilia. Bioinformatics methods and molecular dynamic modeling were able to predict the pathogenic implications of this variation. CONCLUSION: We used whole exome sequencing to find a homozygous WHRN gene variant in a Moroccan family. Numerous bioinformatics methods predict that this modification might result in a change in the WHRN protein's structure.


Asunto(s)
Síndromes de Usher , Humanos , Citoesqueleto , Secuenciación del Exoma , Modelos Moleculares , Mutación/genética , Linaje , Síndromes de Usher/genética
8.
Bioinformation ; 19(7): 795-806, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37901293

RESUMEN

PPARγ agonists play a crucial role in regulating metabolic homeostasis for treating type-2 diabetes (T2D). Due to the adverse side effects associated with thiazolidinediones, a class of PPARγ agonists, there is a growing interest in identifying natural compounds from medicinal plants that have the potential to bind PPARγ. In this study, we extensively investigated Moroccan phytochemicals using computational structure-based screening with the crystal structure of the PPARγ ligand-binding domain (PDB ID: 7awc) to discover novel phytochemicals targeting PPARγ. The docking results of 540 Moroccan phytochemicals were integrated into online databases for further exploitation through in-depth studies. Drug-likeness analysis was performed to assess the phytochemicals drug-like properties. Two promising phytochemicals, 3,4-dicaffeoylquinic acid and Chlorogenic acid, were identified, both exhibiting high docking affinity and unique binding site interactions compared to the established PPARγ full agonist, rosiglitazone. Molecular dynamics simulations of 100 ns were conducted to examine the stability of the complexes formed by both compounds within the PPARγ active site, and their dynamic behavior was compared to the reference structure of PPARγ alone and with rosiglitazone. Binding free energy calculations demonstrated that 3,4-dicaffeoylquinic acid and Chlorogenic acid exhibited higher binding free energy than the reference agonist, suggesting their potential as candidates for experimental validation in future drug discovery efforts targeting PPARγ for the treatment of T2D and metabolic syndrome.

9.
Biochem Genet ; 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37777971

RESUMEN

One of the most prevalent sensorineural disorders, autosomal recessive non-syndromic hearing loss (ARNSHL) which can affect all age groups, from the newborn (congenital) to the elderly (presbycusis). Important etiologic, phenotypic, and genotypic factors can cause deafness. So far, the high genetic variability that explains deafness makes molecular diagnosis challenging. In Morocco, the GJB2 gene is the primary cause of non-syndromic hereditary deafness, while the existence of a variant in the LRTOMT gene is the second cause of this condition. After excluding these two frequently occurring GJB2 and LRTOMT variants, whole-exome sequencing was carried out in two Moroccan consanguineous families with hearing loss. As a result, two novel variants in the TMPRSS3 (c.1078G>A, p. Ala 360Thr) and FOXI1 (c.6C>G, p. Ser 2Arg) genes have been discovered in deaf patients and the pathogenic effect has been anticipated by several bioinformatics and molecular modeling systems. For the first time, these variants are identified in the Moroccan population, showing the population heterogeneity and demonstrating the value of the WES in hearing loss diagnosis.

10.
Comput Biol Chem ; 106: 107937, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37552904

RESUMEN

The process of steroidogenesis plays a vital role in human physiology as it governs the biosynthesis of mineralocorticoids, glucocorticoids, and androgens. These three classes of steroid hormones are primarily produced in the adrenal and gonadal glands through steroidogenesis pathways. Initiated by the side chain cleavage of cholesterol (CLR), this process leads to the conversion of cholesterol into pregnenolone and isocaproic aldehyde. The enzyme CYP11A1, encoded by the CYP11A1 gene, plays a key role in catalyzing the side chain cleavage of CLR. Several single nucleotide polymorphisms (SNPs) have been identified in the CYP11A1 gene, which may predispose carriers to disorders associated with abnormal steroidogenesis. Specifically, missense SNPs in the CYP11A1 gene have the potential to negatively impact the interaction between CYP11A1 and CLR, thus affecting the overall metabolome of steroid hormones. In this computational study, we focused on a specific set of missense SNPs reported in the CYP11A1 gene, aiming to identify variants that directly impact the interaction between CYP11A1 and CLR. The three-dimensional structure of the CYP11A1-CLR complex was obtained from the RCSB Protein Data Bank, while missense SNPs in the CYP11A1 gene were retrieved from Ensembl. To predict the most deleterious variants, we utilized the ConSurf server, SIFT, and PolyPhen. Furthermore, we assessed the impact of induced amino acid (AA) substitutions on the CYP11A1-CLR interaction using the PRODIGY server, PyMol, and Ligplot programs. Additionally, molecular dynamics (MD) simulations were conducted to analyze the effects of deleterious variants on the structural dynamics of the CYP11A1-CLR complex. Among the 8096 retrieved variants, we identified ten missense SNPs (E91K, W147G, R151W, R151Q, S391C, V392M, Q395K, Q416E, R460W, and R460Q) as deleterious for the interaction between CYP11A1 and CLR. MD simulations of the CYP11A1-CLR complexes carrying these deleterious AA substitutions revealed that Q416E, W147G, R460Q, and R460W had the most pronounced impacts on the structural dynamics of the complex. Consequently, these missense SNPs were considered the most deleterious ones. Further functional tests are recommended to assess the impact of these four missense SNPs on the enzymatic activity of CYP11A1. Moreover, Genome-Wide Association Studies (GWAS) should be conducted to determine the significance of their association with abnormal steroidogenesis diseases in various patient groups.


Asunto(s)
Enzima de Desdoblamiento de la Cadena Lateral del Colesterol , Simulación de Dinámica Molecular , Humanos , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/metabolismo , Polimorfismo de Nucleótido Simple , Estudio de Asociación del Genoma Completo , Esteroides , Colesterol , Hormonas
11.
J Biomol Struct Dyn ; 41(24): 14665-14688, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36995171

RESUMEN

By limiting chromosome erosion and end-to-end fusions, telomere integrity is critical for chromosome stability and cell survival. During mitotic cycles or due to environmental stresses, telomeres become progressively shorter and dysfunctional, thus triggering cellular senescence, genomic instability and cell death. To avoid such consequences, the telomerase action, as well as the Shelterin and CST complexes, assure the telomere's protection. Telomeric repeat binding factor 1 (TERF1), which is one of the primary components of the Shelterin complex, binds directly to the telomere and controls its length and function by regulating the telomerase activity. Several reports about TERF1 gene variations have been associated with different diseases, and some of them have linked these variations to male infertility. Hence, this paper can be advantageous to investigate the association between the missense variants of the TERF1 gene and the susceptibility to male infertility. The stepwise prediction of SNPs pathogenicity followed in this study was based on stability and conservation analysis, post-translational modification, secondary structure, functional interaction prediction, binding energy evaluation and finally molecular dynamic simulation. Prediction matching among the tools revealed that out of 18 SNPs, only four (rs1486407144, rs1259659354, rs1257022048 and rs1320180267) were predicted as the most damaging and highly deleterious SNPs affecting the TERF1 protein and its molecular dynamics when interacting with the TERB1 protein by influencing the function, structural stability, flexibility and compaction of the overall complex. Interestingly, these polymorphisms should be considered during genetic screening so they can be used effectively as genetic biomarkers for male infertility diagnosis.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Infertilidad Masculina , Telomerasa , Humanos , Masculino , Proteína 1 de Unión a Repeticiones Teloméricas/genética , Proteína 1 de Unión a Repeticiones Teloméricas/metabolismo , Simulación de Dinámica Molecular , Telomerasa/genética , Telomerasa/metabolismo , Polimorfismo de Nucleótido Simple/genética , Proteínas de Unión a Telómeros/genética , Telómero/metabolismo , Infertilidad Masculina/genética , Complejo Shelterina
12.
Biochem Genet ; 61(5): 1758-1774, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36792840

RESUMEN

Obesity is a global epidemic disease representing the fifth leading cause of death in the world. It was shown that it is caused by the interaction between environmental factors and genes including leptin gene (LEP). This paper aimed to analyze the association between the LEP gene polymorphisms rs7799039 and rs11761556 with obesity in Moroccan individuals as well as to perform an update meta-analysis of this genetic association. Both polymorphisms were genotyped in 146 obesity patients and 104 controls using real-time PCR technique. The genetic association analysis and the comparison of quantitative parameters were carried out using the R language. Moreover, a meta-analysis including 20 genetic association studies was performed using Review Manager 5.3 software. No significant association was found between the polymorphisms rs7799039 and rs11761556 and the risk of obesity. The comparison of biochemical and clinical parameters between the genotypes of the rs7799039 polymorphism, showed a significant increased triglycerides levels in carriers of AA or GA genotypes (P value = 0.040). The meta-analysis showed no significant association between the rs7799039 polymorphism and obesity under all genetic models. In conclusion, the case-control study and meta-analysis demonstrated that the LEP gene polymorphisms rs7799039 and rs11761556 cannot be considered as genetic risk factors for obesity.


Asunto(s)
Leptina , Polimorfismo de Nucleótido Simple , Humanos , Leptina/genética , Estudios de Casos y Controles , Receptores de Leptina/genética , Obesidad/genética , Genotipo , Predisposición Genética a la Enfermedad
13.
J Biomol Struct Dyn ; 41(19): 9503-9522, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-36326488

RESUMEN

Aurora Kinase C (AURKC) is considered an important element in Chromosome Passenger Complex (CPC), its interaction with Inner Centromere Protein (INCENP) plays a critical role in the establishment and the recruitment of a stable CPC during spermatogenesis. Genetic variations of AURKC gene are susceptible to impact AURKC-INCENP interaction, which may affect CPC stability and predispose male subjects to macrozoospermia. In this study, we systematically applied computational approaches using different bioinformatic tools to predict the effect of missense SNPs reported on AURKC gene, we selected the deleterious ones and we introduced their corresponding amino acid substitutions on AURKC protein structure. Then we did a protein-protein docking between AURKC variants and INCENP followed by a structural assessment of each resulting complex using PRODIGY server, Yassara view, Ligplot + and we choose the complexes of the most impactful variants for molecular dynamics (MD) simulation study. Seventeen missense SNPs of AURKC were identified as deleterious between all reported ones. All of them were located on relatively conserved positions on AURKC protein according to Consurf server. Only the four missense SNPs; E91K, D166V, D221Y and G235V were ranked as the most impactful ones and were chosen for MD simulation. D221Y and G235V were responsible for the most remarkable changes on AURKC-INCENP structural stability, therefore, they were selected as the most deleterious ones. Experimental studies are recommended to test the actual effect of these two variants and their actual impact on the morphology of sperm cells.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Infertilidad Masculina , Polimorfismo de Nucleótido Simple , Masculino , Humanos , Aurora Quinasa C/genética , Aurora Quinasa C/metabolismo , Polimorfismo de Nucleótido Simple/genética , Semen/metabolismo , Espermatozoides/metabolismo , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo
14.
Arch Oral Biol ; 142: 105518, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35998423

RESUMEN

OBJECTIVES: To decipher and improve the molecular diagnosis of Hypoplastic Amelogenesis Imperfecta in Morocco. DESIGN: Using whole exome sequencing, we analyzed two Moroccan families with Hypoplastic Amelogenesis Imperfecta. The 2 patients from the first family had dental anomalies and short stature syndrome, brachyolmia and nephrocalcinosis with difference in severity, while the proband of the second family had Hypoplastic Amelogenesis Imperfecta with a suspicion of brachyolmia. RESULTS: We identified two novel LTBP3 homozygous variants, the c.2495delT deletion (p.Phe832SerfsTer36) and the c.3716 G>A (p.Cys1239Tyr) missense variant, respectively. Molecular modelling and stability analyses of the missense variant disclosed a possible destabilization of the wild-type structure. CONCLUSION: Although LTBP3 variants were related to this phenotype in various populations, we report the first LTBP3 variants in the Moroccan population, in families with Hypoplastic Amelogenesis Imperfecta.


Asunto(s)
Amelogénesis Imperfecta , Osteocondrodisplasias , Amelogénesis Imperfecta/diagnóstico por imagen , Amelogénesis Imperfecta/genética , Humanos , Proteínas de Unión a TGF-beta Latente/genética , Linaje
15.
Epilepsy Res ; 185: 106977, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35853334

RESUMEN

PURPOSE: Epilepsy is a common serious brain condition characterized by the abnormal electrical activity of neurons. In most cases, epileptic patients respond to antiepileptic drugs. Approximately, one-third of patients prove medically intractable. The ABCB1 gene is a superfamily of ATP-binding cassette (ABC) transporters that encode a drug-transport protein, lead to cells and organs protects and eliminates toxic agents. We performed this meta-analysis to assess the association between G2677T/A in the ABCB1 gene and the risk of drug resistance in epileptic patients. METHODS: Two online libraries (PubMed and Scopus) were used to identify studies that report the relationship between G2677T/A polymorphism in the MDR1 gene and the risk of antiepileptic drug resistance. The meta-analysis was performed using Review Manager 5.3 software. The pooled odds ratios and 95 % confidence intervals (CIs) were calculated using a random or fixed effects model according to the heterogeneity between studies. RESULTS: A total of 33 eligible studies were included in this meta-analysis which 4192 patients were drug-resistant and 5079 patients were drug-responsive. As a result, a significant association was observed in overall population for the genetic model GG+GA vs AA (OR with 95 % CI = 0,56 [0.34,0.93]; P = 0.02). The subgroup ethnicity analysis showed a significant decrease in the risk of AEDs resistance in the Caucasian population. CONCLUSION: In conclusion, our analysis demonstrates that G2677T/A polymorphism in the ABCB1 gene decreases the risk of drug resistance. More studies are needed in the different ethnic groups to clarify the role of polymorphism in AEDs resistance.


Asunto(s)
Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Epilepsia Refractaria , Epilepsia , Anticonvulsivantes/uso terapéutico , Resistencia a Medicamentos/genética , Epilepsia Refractaria/tratamiento farmacológico , Epilepsia Refractaria/genética , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Genotipo , Humanos , Polimorfismo de Nucleótido Simple/genética
16.
Orphanet J Rare Dis ; 17(1): 197, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35551639

RESUMEN

BACKGROUND: Inherited retinal dystrophies (IRD) and optic neuropathies (ION) are the two major causes world-wide of early visual impairment, frequently leading to legal blindness. These two groups of pathologies are highly heterogeneous and require combined clinical and molecular diagnoses to be securely identified. Exact epidemiological studies are lacking in North Africa, and genetic studies of IRD and ION individuals are often limited to case reports or to some families that migrated to the rest of the world. In order to improve the knowledge of their clinical and genetic spectrums in North Africa, we reviewed published data, to illustrate the most prevalent pathologies, genes and mutations encountered in this geographical region, extending from Morocco to Egypt, comprising 200 million inhabitants. MAIN BODY: We compiled data from 413 families with IRD or ION together with their available molecular diagnosis. The proportion of IRD represents 82.8% of index cases, while ION accounted for 17.8%. Non-syndromic IRD were more frequent than syndromic ones, with photoreceptor alterations being the main cause of non-syndromic IRD, represented by retinitis pigmentosa, Leber congenital amaurosis, and cone-rod dystrophies, while ciliopathies constitute the major part of syndromic-IRD, in which the Usher and Bardet Biedl syndromes occupy 41.2% and 31.1%, respectively. We identified 71 ION families, 84.5% with a syndromic presentation, while surprisingly, non-syndromic ION are scarcely reported, with only 11 families with autosomal recessive optic atrophies related to OPA7 and OPA10 variants, or with the mitochondrial related Leber ION. Overall, consanguinity is a major cause of these diseases within North African countries, as 76.1% of IRD and 78.8% of ION investigated families were consanguineous, explaining the high rate of autosomal recessive inheritance pattern compared to the dominant one. In addition, we identified many founder mutations in small endogamous communities. SHORT CONCLUSION: As both IRD and ION diseases constitute a real public health burden, their under-diagnosis in North Africa due to the absence of physicians trained to the identification of inherited ophthalmologic presentations, together with the scarcity of tools for the molecular diagnosis represent major political, economic and health challenges for the future, to first establish accurate clinical diagnoses and then treat patients with the emergent therapies.


Asunto(s)
Enfermedades del Nervio Óptico , Distrofias Retinianas , Retinitis Pigmentosa , Consanguinidad , Humanos , Mutación/genética , Distrofias Retinianas/genética , Retinitis Pigmentosa/genética
17.
Eur J Med Genet ; 65(6): 104515, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35487419

RESUMEN

Intellectual disability is characterized by a significant impaired intellectual and adaptive functioning, affecting approximately 1-3% of the population, which can be caused by a variety of environmental and genetic factors. In this respect, de novo heterozygous HECW2 variants were associated recently with neurodevelopmental disorders associated to hypotonia, seizures, and absent language. HECW2 encodes an E3 ubiquitin-protein ligase that stabilizes and enhances transcriptional activity of p73, a key factor regulating proliferation, apoptosis, and neuronal differentiation, which are together essential for proper brain development. Here, using whole exome sequencing, we identified a homozygous nonsense HECW2 variant: c.736C > T; p.Arg246* in a proband from a Moroccan consanguineous family, with developmental delay, intellectual disability, hypotonia, generalized tonico-clonic seizures and a persistent tilted head. Thus this study describes the first homozygous HECW2 variant, inherited as an autosomal recessive pattern, contrasting with former reported de novo variants found in HECW2 patients.


Asunto(s)
Discapacidad Intelectual , Malformaciones del Sistema Nervioso , Trastornos del Neurodesarrollo , Homocigoto , Humanos , Discapacidad Intelectual/genética , Hipotonía Muscular/genética , Trastornos del Neurodesarrollo/genética , Convulsiones/genética , Ubiquitina-Proteína Ligasas/genética
18.
Biomed Res Int ; 2022: 1664825, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35342767

RESUMEN

Meiotic chromosomes endure rapid prophase movements that ease the formation of interhomologue recombination intermediates that drive synapsis, crossing over, and segregation process. To generate these fast moves, the meiotic telomere complex (MTC) enables telomere-inner nuclear membrane attachment during meiotic prophase I and transfers cytoskeletal signals via another complex: the LINC complex. Furthermore, disruption or mutations of any of the MTC genes (TERB1, TERB2, and MAJIN) alters telomere association with the nuclear envelope leading to impairment of homologous pairing and synapsis, a meiotic arrest, and consequently to male infertility. To decipher the effect of TERB1, TERB2, and MAJIN missense mutations on protein structure, stability, and function, different bioinformatic tools were used in this study including VEP, Mutabind2, Haddock, Prodigy, Ligplot, ConSurf, DUET and MusiteDeep. In total, thirty mutations were predicted to be deleterious using VEP web server: seventeen for TERB1, eleven for TERB2, and two for MAJIN. All these single nucleotide polymorphisms were further analyzed and only 11 SNPs (W8R, G25R, P649A, I624T, C618R, F607V, S604G, C592Y, C592R, G187W, and R53C) were found to be the most damaging by at least six software tools and exert deleterious effect on the TERB1, TERB2, and MAJIN protein structures and likely functions. They revealed high conservation, less stability, and having a role in posttranslational modifications. This in silico approach provides information to gain further insights about variants that might affect stability, change binding affinity, and edit protein-protein interactions to facilitate their identification and functional characterization associated with male infertility.


Asunto(s)
Infertilidad Masculina , Proteínas de Unión a Telómeros , Proteínas de Ciclo Celular/genética , Humanos , Infertilidad Masculina/genética , Masculino , Meiosis/genética , Polimorfismo de Nucleótido Simple/genética , Telómero/metabolismo , Proteínas de Unión a Telómeros/genética
19.
Biomed Res Int ; 2022: 1141280, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35281597

RESUMEN

Leukocyte adhesion deficiency type 1 (LAD1) is a rare autosomal recessive hereditary disorder characterized by recurrent infections, impaired pus formation, delayed wound healing, omphalitis, and delayed separation of the umbilical cord as hallmark features of the disease. It results from mutations in the integrin ß2 subunit gene ITGB2, which encodes the integrin beta chain-2 protein CD18. In this study, we aimed to investigate the case of a five-month-old boy who presented with a clinical phenotype and flow cytometry results suggesting LAD1 disease. Sanger sequencing of all exons and intron boundaries of ITGB2 identified a novel in-frame deletion in exon 7 (ITGB2 c.844_846delAAC, p.Asn282del) in the patient. The p.Asn282del mutation was heterozygous in the child's parents, whereas it was absent in the 96 control individuals from North Africa. This variant was evaluated by two in silico mutation analysis tools, PROVEAN and MutationTaster, which predicted that the mutation was likely to be pathogenic. In addition, molecular modeling with the YASARA View software suggested that this novel mutation may affect the structure of integrin beta-2 and, subsequently, its interaction with integrin alpha-X. In summary, we report a novel pathogenic mutation p.Asn282del associated with LAD1 that expands the mutation diversity of ITGB2 and suggest the combination of flow cytometry and ITGB2 sequencing as a first-line diagnostic approach for LAD disease.


Asunto(s)
Antígenos CD18 , Síndrome de Deficiencia de Adhesión del Leucocito , Antígenos CD18/genética , Antígenos CD18/metabolismo , Humanos , Lactante , Síndrome de Deficiencia de Adhesión del Leucocito/diagnóstico , Síndrome de Deficiencia de Adhesión del Leucocito/genética , Síndrome de Deficiencia de Adhesión del Leucocito/patología , Masculino , Mutación/genética , Fenotipo
20.
Diabetol Metab Syndr ; 14(1): 25, 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35109885

RESUMEN

BACKGROUND: Variants in the Hepatocyte Nuclear Factor 1 Alpha gene (HNF1A) are associated with lipoproteins levels and type 2 diabetes. In this study, we aimed to assess the association of HNF1A gene and haplotypes with the metabolic syndrome (MetS) and its components through an association study in the Tunisian population as well as by a meta-analysis. METHODS: A total of 594 Tunisian individuals were genotyped for three variants (rs1169288, rs2464196 and rs735396) located in HNF1A gene using KASPar technology. Statistical analyses were performed with R software. The association was furthermore evaluated through a meta-analysis of our results with those obtained in a Moroccan population. RESULTS: Our results showed no association between HNF1A variants and MetS in the Tunisian population. However, a significant association was observed between the variant rs735396 and a higher waist circumference. The stratified analysis according to the sex highlighted a significant association between the variant rs1169288 and high cholesterol levels only in women. Similarly, Haplotype analysis showed an association between the HNF1A minor haplotype and high total cholesterol mainly in women. Finally, our meta-analysis showed no association between HNF1A variants and MetS. CONCLUSIONS: Our findings exclude the involvement of the three HNF1A variants rs1169288, rs2464196 and rs735396 in the susceptibility to MetS in our studied Tunisian population but emphasize the role of these variants in the cholesterol homeostasis with sex-specific differences, which may serve to rise clinical consideration to early statin therapy in women carrying these genetic variants.

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