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1.
Viruses ; 15(9)2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37766339

RESUMO

Commencing in December 2019 with the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), three years of the coronavirus disease 2019 (COVID-19) pandemic have transpired. The virus has consistently demonstrated a tendency for evolutionary adaptation, resulting in mutations that impact both immune evasion and transmissibility. This ongoing process has led to successive waves of infections. This study offers a comprehensive assessment spanning genetic, phylogenetic, phylodynamic, and phylogeographic dimensions, focused on the trajectory of the SARS-CoV-2 epidemic in Cyprus. Based on a dataset comprising 4700 viral genomic sequences obtained from affected individuals between October 2021 and October 2022, our analysis is presented. Over this timeframe, a total of 167 distinct lineages and sublineages emerged, including variants such as Delta and Omicron (1, 2, and 5). Notably, during the fifth wave of infections, Omicron subvariants 1 and 2 gained prominence, followed by the ascendancy of Omicron 5 in the subsequent sixth wave. Additionally, during the fifth wave (December 2021-January 2022), a unique set of Delta sequences with genetic mutations associated with Omicron variant 1, dubbed "Deltacron", was identified. The emergence of this phenomenon initially evoked skepticism, characterized by concerns primarily centered around contamination or coinfection as plausible etiological contributors. These hypotheses were predominantly disseminated through unsubstantiated assertions within the realms of social and mass media, lacking concurrent scientific evidence to validate their claims. Nevertheless, the exhaustive molecular analyses presented in this study have demonstrated that such occurrences would likely lead to a frameshift mutation-a genetic aberration conspicuously absent in our provided sequences. This substantiates the accuracy of our initial assertion while refuting contamination or coinfection as potential etiologies. Comparable observations on a global scale dispelled doubt, eventually leading to the recognition of Delta-Omicron variants by the scientific community and their subsequent monitoring by the World Health Organization (WHO). As our investigation delved deeper into the intricate dynamics of the SARS-CoV-2 epidemic in Cyprus, a discernible pattern emerged, highlighting the major role of international connections in shaping the virus's local trajectory. Notably, the United States and the United Kingdom were the central conduits governing the entry and exit of the virus to and from Cyprus. Moreover, notable migratory routes included nations such as Greece, South Korea, France, Germany, Brazil, Spain, Australia, Denmark, Sweden, and Italy. These empirical findings underscore that the spread of SARS-CoV-2 within Cyprus was markedly influenced by the influx of new, highly transmissible variants, triggering successive waves of infection. This investigation elucidates the emergence of new waves of infection subsequent to the advent of highly contagious and transmissible viral variants, notably characterized by an abundance of mutations localized within the spike protein. Notably, this discovery decisively contradicts the hitherto hypothesis of seasonal fluctuations in the virus's epidemiological dynamics. This study emphasizes the importance of meticulously examining molecular genetics alongside virus migration patterns within a specific region. Past experiences also emphasize the substantial evolutionary potential of viruses such as SARS-CoV-2, underscoring the need for sustained vigilance. However, as the pandemic's dynamics continue to evolve, a balanced approach between caution and resilience becomes paramount. This ethos encourages an approach founded on informed prudence and self-preservation, guided by public health authorities, rather than enduring apprehension. Such an approach empowers societies to adapt and progress, fostering a poised confidence rooted in well-founded adaptation.


Assuntos
COVID-19 , Coinfecção , Humanos , SARS-CoV-2/genética , Chipre/epidemiologia , Filogenia , COVID-19/epidemiologia , Genômica , Pandemias
2.
Metabolites ; 13(7)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37512526

RESUMO

Microbiota and the metabolites they produce within the large intestine interact with the host epithelia under the influence of a range of host-derived metabolic, immune, and homeostatic factors. This complex host-microbe interaction affects intestinal tumorigenesis, but established microbial or metabolite profiles predicting colorectal cancer (CRC) risk are missing. Here, we aimed to identify fecal bacteria, volatile organic compounds (VOC), and their associations that distinguish healthy (non-adenoma, NA) from CRC prone (high-risk adenoma, HRA) individuals. Analyzing fecal samples obtained from 117 participants ≥15 days past routine colonoscopy, we highlight the higher abundance of Proteobacteria and Parabacteroides distasonis, and the lower abundance of Lachnospiraceae species, Roseburia faecis, Blautia luti, Fusicatenibacter saccharivorans, Eubacterium rectale, and Phascolarctobacterium faecium in the samples of HRA individuals. Volatolomic analysis of samples from 28 participants revealed a higher concentration of five compounds in the feces of HRA individuals, isobutyric acid, methyl butyrate, methyl propionate, 2-hexanone, and 2-pentanone. We used binomial logistic regression modeling, revealing 68 and 96 fecal bacteria-VOC associations at the family and genus level, respectively, that distinguish NA from HRA endpoints. For example, isobutyric acid associations with Lachnospiraceae incertae sedis and Bacteroides genera exhibit positive and negative regression lines for NA and HRA endpoints, respectively. However, the same chemical associates with Coprococcus and Colinsella genera exhibit the reverse regression line trends. Thus, fecal microbiota and VOC profiles and their associations in NA versus HRA individuals indicate the significance of multiple levels of analysis towards the identification of testable CRC risk biomarkers.

3.
Cardiooncology ; 8(1): 16, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071532

RESUMO

Breast cancer patients are at a particularly high risk of cardiotoxicity from chemotherapy having a detrimental effect on quality-of-life parameters and increasing the risk of mortality. Prognostic biomarkers would allow the management of therapies to mitigate the risks of cardiotoxicity in vulnerable patients and a key potential candidate for such biomarkers are microRNAs (miRNA). miRNAs are post-transcriptional regulators of gene expression which can also be released into the circulatory system and have been associated with the progression of many chronic diseases including many types of cancer. In this review, the evidence for the potential application of miRNAs as biomarkers for chemotherapy-induced cardiotoxicity (CIC) in breast cancer patientsis evaluated and a simple meta-analysis is performed to confirm the replication status of each reported miRNA. Further selection of miRNAs is performed by reviewing the reported associations of each miRNA with other cardiovascular conditions. Based on this research, the most representative panels targeting specific chemotherapy agents and treatment regimens are suggested, that contain several informative miRNAs, including both general markers of cardiac damage as well as those for the specific cancer treatments.

4.
Genes (Basel) ; 13(2)2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35205422

RESUMO

Polycystic ovary syndrome (PCOS) is a very common endocrine condition in women in India. Gut microbiome alterations were shown to be involved in PCOS, yet it is remarkably understudied in Indian women who have a higher incidence of PCOS as compared to other ethnic populations. During the regional PCOS screening program among young women, we recruited 19 drug naive women with PCOS and 20 control women at the Sher-i-Kashmir Institute of Medical Sciences, Kashmir, North India. We profiled the gut microbiome in faecal samples by 16S rRNA sequencing and included 40/58 operational taxonomic units (OTUs) detected in at least 1/3 of the subjects with relative abundance (RA) ≥ 0.1%. We compared the RAs at a family/genus level in PCOS/non-PCOS groups and their correlation with 33 metabolic and hormonal factors, and corrected for multiple testing, while taking the variation in day of menstrual cycle at sample collection, age and BMI into account. Five genera were significantly enriched in PCOS cases: Sarcina, Megasphaera, and previously reported for PCOS Bifidobacterium, Collinsella and Paraprevotella confirmed by different statistical models. At the family level, the relative abundance of Bifidobacteriaceae was enriched, whereas Peptococcaceae was decreased among cases. We observed increased relative abundance of Collinsella and Paraprevotella with higher fasting blood glucose levels, and Paraprevotella and Alkalibacterium with larger hip, waist circumference, weight, and Peptococcaceae with lower prolactin levels. We also detected a novel association between Eubacterium and follicle-stimulating hormone levels and between Bifidobacterium and alkaline phosphatase, independently of the BMI of the participants. Our report supports that there is a relationship between gut microbiome composition and PCOS with links to specific reproductive health metabolic and hormonal predictors in Indian women.


Assuntos
Microbioma Gastrointestinal , Síndrome do Ovário Policístico , Bacteroidetes/genética , Bifidobacterium/genética , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Humanos , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , RNA Ribossômico 16S/genética
5.
Ecotoxicol Environ Saf ; 232: 113213, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35085885

RESUMO

Current knowledge on the capacity of plastics as vectors of microorganisms and their ability to transfer microorganisms between different habitats (i.e. air, soil and river) is limited. The objective of this study was to characterise the evolution of the bacterial community adhered to environmental plastics [low-density polyethylene (LDPE)] across different environments from their point of use to their receiving environment destination in the sea. The study took place in a typical Mediterranean intermittent river basin in Larnaka, Cyprus, characterised by a large greenhouse area whose plastic debris may end up in the sea due to mismanagement. Five locations were selected to represent the environmental fate of greenhouse plastics from their use, through their abandonment in soil and subsequent transport to the river and the sea, taking samples of plastics and the surrounding environments (soil and water). The bacterial community associated with each sample was studied by 16S rRNA metabarcoding; also, the main physicochemical parameters in each environmental compartment were analysed to understand these changes. The identification and chemical changes in greenhouse plastics were tracked using Attenuated Total Reflection Fourier Transform Infra-red spectroscopy (ATR-FTIR). Scanning Electron Microscope (SEM) analysis demonstrated an evolution of the biofilm at each sampling location. ß-diversity studies showed that the bacterial community adhered to plastics was significantly different from that of the surrounding environment only in samples taken from aqueous environments (freshwater and sea) (p-value p-value > 0.05). The environmental parameters (pH, salinity, total nitrogen and total phosphorus) explained the differences observed at each location to a limited extent. Furthermore, bacterial community differences among samples were lower in plastics collected from the soil than in plastics taken from rivers and seawater. Six genera (Flavobacterium, Altererythrobacter, Acinetobacter, Pleurocapsa, Georgfuchsia and Rhodococcus) were detected in the plastic, irrespective of the sampling location, confirming that greenhouse plastics can act as possible vectors of microorganisms between different environments: from their point of use, through a river system to the final coastal receiving environment. In conclusion, this study confirms the ability of greenhouse plastics to transport bacteria, including pathogens, between different environments. Future studies should evaluate these risks by performing complete sequencing metagenomics to decipher the functions of the plastisphere.


Assuntos
Plásticos , Água do Mar , Bactérias/genética , RNA Ribossômico 16S/genética , Rios , Água do Mar/microbiologia
6.
Viruses ; 15(1)2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36680148

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in December 2019 resulted in the coronavirus disease 2019 (COVID-19) pandemic, which has had devastating repercussions for public health. Over the course of this pandemic, the virus has continuously been evolving, resulting in new, more infectious variants that have frequently led to surges of new SARS-CoV-2 infections. In the present study, we performed detailed genetic, phylogenetic, phylodynamic and phylogeographic analyses to examine the SARS-CoV-2 epidemic in Cyprus using 2352 SARS-CoV-2 sequences from infected individuals in Cyprus during November 2020 to October 2021. During this period, a total of 61 different lineages and sublineages were identified, with most falling into three groups: B.1.258 & sublineages, Alpha (B.1.1.7 & Q. sublineages), and Delta (B.1.617.2 & AY. sublineages), each encompassing a set of S gene mutations that primarily confer increased transmissibility as well as immune evasion. Specifically, these lineages were coupled with surges of new infections in Cyprus, resulting in the following: the second wave of SARS-CoV-2 infections in Cyprus, comprising B.1.258 & sublineages, during late autumn 2020/beginning of winter 2021; the third wave, comprising Alpha (B.1.1.7 & Q. sublineages), during spring 2021; and the fourth wave, comprising Delta (B.1.617.2 & AY. sublineages) during summer 2021. Additionally, it was identified that these lineages were primarily imported from and exported to the UK, Greece, and Sweden; many other migration links were also identified, including Switzerland, Denmark, Russia, and Germany. Taken together, the results of this study indicate that the SARS-CoV-2 epidemic in Cyprus was characterized by successive introduction of new lineages from a plethora of countries, resulting in the generation of waves of infection. Overall, this study highlights the importance of investigating the spatiotemporal evolution of the SARS-CoV-2 epidemic in the context of Cyprus, as well as the impact of protective measures placed to mitigate transmission of the virus, providing necessary information to safeguard public health.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Chipre/epidemiologia , Filogenia , COVID-19/epidemiologia , Genômica , Pandemias
7.
World J Pediatr ; 16(2): 168-176, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31583533

RESUMO

BACKGROUND: Next-generation sequencing has revolutionized our perspective on the gut microbiome composition, revealing the true extent of the adverse effects of antibiotics. The impact of antibiotic treatment on gut microbiota must be considered and researched to provide grounds for establishing new treatment strategies that are less devastating on commensal bacteria. This study investigates the impact on gut microbiome when a commonly used antibiotic, azithromycin is administered, as well as uncovers the benefits induced when it is used in combination with lactulose, a prebiotic known to enhance the proliferation of commensal microbes. METHODS: 16S rRNA gene sequencing analysis of stool samples obtained from 87 children treated with azithromycin in combination with or without lactulose have been determined. Children's gut microbial profile was established at the pre- and post-treatment stage. RESULTS: Azithromycin caused an increase in the relative abundance of opportunistic pathogens such as Streptococcus that was evident 60 days after treatment. While few days after treatment, children who also received lactulose started to show a higher relative abundance of saccharolytic bacteria such as Lactobacillus, Enterococcus, Anaerostipes, Blautia and Roseburia, providing a protective role against opportunistic pathogens. In addition, azithromycin-prebiotic combination was able to provide a phylogenetic profile more similar to the pre-treatment stage. CONCLUSION: It is suggested that during azithromycin treatment, lactulose is able to reinstate the microbiome equilibrium much faster as it promotes saccharolytic microbes and provides a homeostatic effect that minimizes the opportunistic pathogen colonization.


Assuntos
Antibacterianos/farmacologia , Azitromicina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Lactulose/farmacologia , Prebióticos , Adolescente , Antibacterianos/administração & dosagem , Azitromicina/administração & dosagem , Criança , Pré-Escolar , Método Duplo-Cego , Combinação de Medicamentos , Humanos , Lactulose/administração & dosagem
8.
Int J Endocrinol ; 2017: 8984365, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28487735

RESUMO

Heterozygosity for CYP21A2 mutations in females is possibly related to increased risk of developing clinical hyperandrogenism. The present study was designed to seek evidence on the phenotype-genotype correlation in female children, adolescents, and women with CYP21A2 mutations and variants in the 3'UTR region of the gene. Sixty-six patients out of the 169 were identified as carriers of CYP21A2 mutations. Higher values of stimulated 17 hydroxyprogesterone (17-OHP) levels were found in the carriers of the p.Val281Leu mutation compared to the carriers of other mutations (mean: 24.7 nmol/l versus 15.6 nmol/l). The haplotype of the ∗52C>T, ∗440C>T, and ∗443T>C in the 3'UTR was identical in all heterozygous patients with p.Val281Leu and the haplotype of the ∗12C>T and ∗52C>T was identical in all heterozygous patients with the p.Gln318∗. In conclusion, hyperandrogenaemic females are likely to bear heterozygous CYP21A2 mutations. Carriers of the mild p.Val281Leu mutation are at higher risk of developing hyperandrogenism than the carriers of more severe mutations. The identification of variants in the 3'UTR of CYP21A2 in combination with the heterozygous mutation may be associated with the mild form of nonclassic congenital adrenal hyperplasia and reveal the importance of analyzing the CYP21A2 untranslated regions for the appropriate management of this category of patients.

9.
J Genet ; 96(1): 155-160, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28360400

RESUMO

The prevalence of genetic variants associated to cutaneous melanoma (CM) has never been determined within Cypriot melanomas. This study evaluates the frequency of variants in cyclin-dependent kinase inhibitor 2A (CDKN2A) and melanocortin-1 receptor (MC1R) in 32 patients diagnosed with CM. Other characteristics and risk factors were also assessed. CDKN2A p.Ala148Thr was detected in three of 32 patients, while the control group revealed no variations within CDKN2A. MC1R screening in 32 patients revealed the following variations: p.Val60Leu in 11 patients, p.Arg142His in four patients, p.Thr314Thr in one patient, p.Arg160Trp in one patient, p.Val92Met/p.Thr314Thr in one patient and p.Val92Met/p.Arg142His/p.Thr314Thr in one patient. The control group revealed only p.Val60Leu (in 10 of 45 individuals), which is frequently found in general populations. Two unrelated patients carried CDKN2A p.Ala148Thr in combination with MC1R p.Arg142His, suggesting digenic inheritance that may provide evidence of different gene variants acting synergistically to contribute for CM development. This study confirms the presence of CDKN2A and MC1R variants among Cypriot melanomas and supports existing evidence of a role for these variants in susceptibility to melanoma.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Melanoma/diagnóstico , Melanoma/genética , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , Adulto , Idoso , Alelos , Substituição de Aminoácidos , Feminino , Genótipo , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Melanoma Maligno Cutâneo
10.
J Genet ; 95(4): 761-766, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27994174

RESUMO

Familial Mediterranean fever (FMF) has traditionally been considered as a monogenic autosomal recessive disorder caused by mutations in the MEFV gene with highest incidence among Mediterranean populations. In a considerable number of patients with typical FMF, only one MEFV mutation was identified and the possibility that more than one autoinflammatory gene may be responsible for their disease was investigated. In the present study, an extensive search for possible mutations in three hereditary recurrent fever (HRF) genes was performed in 128 MEFV heterozygous Greek-Cypriots clinically diagnosed based on their phenotype with FMF-like disease from a previous study. Sequence analysis was performed for MVK, TNFRSF1A and NLRP3 genes which is also known to cause HRFs. In total, three patients were identified with heterozygous mutations and a second mutation in an autoinflammatory gene. Two patients carried a MEFV mutation and a NLRP3 mutation, and an additional third carried a MEFV mutation and a TNFRSF1A mutation. Patient 1 carried MEFV p.[Val726Ala] (NM_000243.2:c.2177T>C) and NLRP3 p.[Val198Met] (NM_001243133.1:c.592G>A) variants and patient 2 carried MEFV p.[Glu148Gln] (NM_000243.2:c.442G>C) variant which is of uncertain significance and NLRP3 p.[Arg176Trp] (NM_001243133.1:c.526C>T). Lastly, patient 3 was identified to carry MEFV p.[Met694Val] (NM_000243.2:c.2080A>G) and TNFRSF1A p.[Arg121Gln] (NM_001065.3:c.362G>A) variants. The results from this study indicate that screening of genes known to cause HRFs in patients already identified with a single MEFV mutation, can reveal quite rare but potentially causative mutational combinations at different loci. Such interaction provide further evidence for possible locus-locus interactions and phenotypes resulting from digenic inheritance.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Inflamação/genética , Padrões de Herança , Adolescente , Adulto , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/tratamento farmacológico , Febre Familiar do Mediterrâneo/genética , Feminino , Humanos , Inflamação/diagnóstico , Inflamação/tratamento farmacológico , Masculino , Mutação , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Linhagem , Fenótipo , Pirina/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Adulto Jovem
11.
Hormones (Athens) ; 15(3): 445-452, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27394708

RESUMO

OBJECTIVE: Heterozygous mutations on the melanocortin-4-receptor gene (MC4R) are the most frequent cause of monogenic obesity. We describe a novel MC4R deletion in a girl with severe early onset obesity, tall stature, pale skin and red hair. CASE REPORT: Clinical and hormonal parameters were evaluated in a girl born full-term by non-consanguineous parents. Her body mass index (BMI) at presentation (3 years) was 30 kg/m2 (z-score: +4.5SDS). By the age of 5.2 years, she exhibited extreme linear growth acceleration and developed hyperinsulinemia. METHODS: Direct sequencing of the MC4R, MC1Rand for the knownFTOsingle nucleotide polymorphism (SNP) rs9939609was performed for the patient and her family. RESULTS: A novel heterozygous MC4R p.Met215del (c.643_645delATG) deletion was identified in the patient, her father and her brother, both of whom exhibited a milder phenotype. 3D structural dynamic simulation studies investigated the conformational changes induced by the p.Met215del. The patient and her mother were also found to be carriers of the obesity risk associated FTOrs9939609SNP. Finally, the identification of the known p.Arg160Trp MC1Rvariant in the patient accounts for the red hair and pale skin phenotypic features. CONCLUSION: The p.Met215del causes global conformational and functional changes as it is localized at the alpha-helical transmembrane regions and the membrane spanning regions of the beta-barrel. This novel mutation produces a severe overgrowth phenotype that is apparent as from infancy and is progressive in childhood. The additional negative effect of environmental and unhealthy lifestyle habits as well as a possible co-interaction of FTOrs9939609 SNP may worsen the phenotype.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Deleção de Genes , Obesidade Infantil/genética , Polimorfismo de Nucleotídeo Único , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/genética , Idade de Início , Índice de Massa Corporal , Criança , Pré-Escolar , Comportamento Alimentar , Feminino , Predisposição Genética para Doença , Cor de Cabelo/genética , Hereditariedade , Heterozigoto , Humanos , Hiperfagia/genética , Hiperfagia/fisiopatologia , Obesidade Infantil/diagnóstico , Obesidade Infantil/fisiopatologia , Linhagem , Fenótipo , Conformação Proteica , Receptor Tipo 4 de Melanocortina/química , Receptor Tipo 4 de Melanocortina/metabolismo , Índice de Gravidade de Doença , Pigmentação da Pele/genética , Relação Estrutura-Atividade
12.
Hormones (Athens) ; 15(2): 235-242, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27376426

RESUMO

OBJECTIVE: Congenital adrenal hyperplasia (CAH) is an endocrine autosomal recessive disorder with various symptoms of diverse severity. Mild hyperandrogenemia is the most commonclinical feature in non-classic CAH patients and 95% of the cases are identified by mutations in the CYP21A2 gene. In the present study, the second most common cause for non-classic CAH (NC-CAH), 11ß-hydroxylase deficiency due to mutations in the CYP11B1 gene, is investigated. DESIGN: Screening of the CYP21A2 and CYP11B1 genes by direct sequencing was carried out for the detection of possible genetic defects in patients with suspected CAH. RES ULTS: It wasobserved that CYP11B1 variants co-exist only in rare cases along with mutations in CYP21A2 in patients clinically diagnosed with CAH. A total of 23 NC-CAH female patients out of 75 were identified with only one mutation in the CYP21A2 gene. The novel CYP11B1 gene mutation, p.Val484Asp, was identified in a patient with CAH in the heterozygous state. The structural characterization of the novel p.Val484Asp was found to likely cause distortion of the surrounding beta sheet and indirect destabilization of the cavity that occurs on the opposite face of the structural elements, leading to partial impairment of the enzymatic activity. CONCLUSIONS: CYP21A2 gene mutations are the most frequent genetic defects in cases of NC-CAH even when these patients are in the heterozygous state. These mutations have a diverse phenotype giving rise to a variable extent of cortisol synthesis impairment; it is also clear that CYP11B1 mutants are a rare type of defects causing CAH.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Análise Mutacional de DNA , Testes Genéticos/métodos , Hiperandrogenismo/genética , Mutação , Esteroide 11-beta-Hidroxilase/genética , Adolescente , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/enzimologia , Criança , Pré-Escolar , Simulação por Computador , Estabilidade Enzimática , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Hiperandrogenismo/diagnóstico , Hiperandrogenismo/enzimologia , Modelos Moleculares , Fenótipo , Valor Preditivo dos Testes , Conformação Proteica em Folha beta , Esteroide 11-beta-Hidroxilase/química , Esteroide 11-beta-Hidroxilase/metabolismo , Esteroide 21-Hidroxilase/genética , Relação Estrutura-Atividade
13.
Am J Med Genet A ; 170(3): 754-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26728615

RESUMO

Steinfeld syndrome (MIM #184705) was first reported in 1982. It is characterised by holoprosencephaly and limb defects, however other anomalies may also be present. Following the initial description, three further cases have been reported in the literature. We report on a 23-year-old girl, with features of microform holoprosencephaly and bilateral congenital elbow dislocation in association with hypoplastic radial heads. She was identified to have a variant in the CDON gene inherited from her father who had ocular hypotelorism, but no other clinical features. We discuss the clinical features of Steinfeld syndrome, and broaden the phenotypic spectrum of this condition. Structural analysis suggests that this variant could lead to destabilisation of binding of CDON with hedgehog proteins. Further work needs to be done to confirm whether mutations in the CDON gene are the cause of Steinfeld syndrome.


Assuntos
Cardiopatias Congênitas/diagnóstico , Holoprosencefalia/diagnóstico , Deformidades Congênitas dos Membros/diagnóstico , Fenótipo , Sequência de Aminoácidos , Encéfalo/patologia , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Hibridização Genômica Comparativa , Fácies , Feminino , Cardiopatias Congênitas/genética , Heterozigoto , Holoprosencefalia/genética , Humanos , Deformidades Congênitas dos Membros/genética , Imageamento por Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Conformação Proteica , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Adulto Jovem
14.
Clin Endocrinol (Oxf) ; 84(1): 80-4, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26173472

RESUMO

BACKGROUND: The onset of puberty is influenced by the interplay of stimulating and restraining factors, many of which have a genetic origin. Premature activation of the GnRH secretion in central precocious puberty (CPP) may arise either from gain-of-function mutations of the KISS1 and KISS1R genes or from loss-of-function manner mutations of the MKRN3 gene leading to MKRN3 deficiency. OBJECTIVE: To explore the genetic causes responsible for CPP and the potential role of the RING finger protein 3 (MKRN3) gene. DESIGN AND PATIENTS: We investigated potential sequence variations in the intronless MKRN3 gene by Sanger sequencing of the entire 507 amino acid coding region of exon 1 in a family with two affected girls presented with CPP at the age of 6 and 5·7 years, respectively. RESULTS: A novel heterozygous g.Gly312Asp missense mutation in the MKRN3 gene was identified in these siblings. The imprinted MKRN3 missense mutation was also identified as expected in the unaffected father and followed as expected an imprinted mode of inheritance. In silico analysis of the altered missense variant using the computational algorithms Polyphen2, SIFT and Mutation Taster predicted a damage and pathogenic alteration causing CPP. The pathogenicity of the alteration at the protein level via an in silico structural model is also explored. CONCLUSION: A novel mutation in the MKRN3 gene in two sisters with CPP was identified, supporting the fundamental role of this gene in the suppression of the hypothalamic GnRH neurons.


Assuntos
Simulação por Computador , Predisposição Genética para Doença/genética , Mutação de Sentido Incorreto , Puberdade Precoce/genética , Ribonucleoproteínas/genética , Sequência de Aminoácidos , Criança , Pré-Escolar , Análise Mutacional de DNA , Saúde da Família , Feminino , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Conformação Proteica , Ribonucleoproteínas/química , Irmãos , Ubiquitina-Proteína Ligases
16.
Ann Hum Genet ; 79(1): 20-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25393764

RESUMO

Familial Mediterranean fever (FMF) is caused by mutations in the MEFV gene and the spectrum of mutations among Greek-Cypriots with FMF-related symptoms was examined. Sequence analysis for exons 2, 3, 5, and 10 of the MEFV gene was performed in a cohort of 593 patients. A total of 70 patients carried mutations in the homozygote or compound heterozygote state, 128 were identified with one MEFV mutation and 395 had no mutations. Of the 268 identified alleles, p.Val726Ala (27.61%) was the most frequent followed by p.Met694Val (19.40%). The missense mutations p.Arg761His (3.73%) and p.Ala744Ser (2.24%) were identified as the rarest. An interesting finding is the high frequency (18.28%) of the complex p.Phe479Leu-p.Glu167Asp that was identified in 49 of the mutated alleles. The MEFV genotypes did not follow a binomial distribution and proved not to satisfy the HWE (P < 0.001). The high percentage (66.61%) of patients with unidentified mutations could be due to mutations in the rest of the coding or noncoding MEFV gene or due to mutations in other genes that are also causing Hereditary Recurrent Fevers. Results from this work indicate the high incidence of FMF in Cyprus and describe the spectrum of the mutations which occur in the country.


Assuntos
Proteínas do Citoesqueleto/genética , Febre Familiar do Mediterrâneo/genética , Adulto , Alelos , Estudos de Coortes , Chipre , Análise Mutacional de DNA , Éxons , Feminino , Frequência do Gene , Genótipo , Heterozigoto , Homozigoto , Humanos , Masculino , Mutação de Sentido Incorreto , Pirina
17.
Indian J Endocrinol Metab ; 18(Suppl 1): S72-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25538881

RESUMO

OBJECTIVES: The objective was to seek evidence on the prevalence and consequences of heterozygous CYP21A2 mutations in girls, adolescent, and adult females with clinical manifestation of androgen excess. PATIENTS AND METHODS: The study included 64 girls diagnosed with premature adrenarche (PA) in childhood and 141 females with clinical hyperandrogenemia manifested in adolescence or adulthood. Direct DNA sequencing and multiplex ligation-dependent probe amplification analysis were used to identify mutations in the CYP21A2 gene. RESULTS: (1) Thirty-four patients were diagnosed with nonclassical-congenital adrenal hyperplasia (NC-CAH) based on the 17-hydroxyprogesterone (17-OHP) levels and the presence of two mutations in CYP21A2 and therefore were excluded from the study, 66 were found to be heterozygotes and finally 105 had no identifiable mutations. The most frequent mutations among the carriers were the mild p.Val281 Leu and p.Qln318stop. Higher levels of mean stimulated 17-OHP were found in the carriers of the p.Val281 Leu. (2) A notable increased allelic frequency for the known p.Asn493 Ser polymorphism was observed in the pool of females with hyperandrogenemia in whom no mutation was identified. (3) In girls, who presented early with PA, 26.6% were diagnosed with NC-CAH and carried two mutations, 28.7% were identified as heterozygotes 43.7% had no identifiable genetic defect in the translated region of the CYP21A2 gene. On the contrary, in the group of 141 females with late onset hyperandrogenemia, the presence of 2 mutations was detected in 12%, 1 mutation in 33.4% and no mutation in 54.6%. CONCLUSIONS: The carrier status for 21-OHD, may be an important factor in the variable phenotype of hyperandrogenism and may be a contributing factor for the early manifestation of the disease.

19.
J Pediatr Endocrinol Metab ; 26(11-12): 1189-95, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23846138

RESUMO

OBJECTIVES: Camurati-Engelmann disease (CED) is a rare form of progressive diaphyseal dysplasia as a result of mutations in the transforming growth factor gene TGFbeta1 on chromosome 19q13.1-q13.3. Endocrine complications such as osteoporosis, vitamin D deficiency, delayed puberty, and hypogonadotrophic hypogonadism may be present. METHODS: Genetic analysis of the TGFbeta1 gene revealed a heterozygous missense mutation p.R218C in exon 4 of chromosome 19q13.1-q13.3 in a 14-year-old girl who presented with typical symptoms of CED, hyperprolactinaemia, and menstrual irregularity. RESULTS: The patient responded well to prednisone 5 mg/kg/day, as well as calcium and vitamin D supplements. CONCLUSIONS: The role of p.R218C in TGFbeta1 on the mechanism of the disease, and the complications of it in bones and endocrine glands, remains unclear. Early recognition as well as a detailed understanding of the pathogenesis of the disease are important for future treatment options and a better quality of life of such patients.


Assuntos
Osso e Ossos/metabolismo , Síndrome de Camurati-Engelmann/genética , Glândulas Endócrinas/metabolismo , Mutação de Sentido Incorreto , Fator de Crescimento Transformador beta1/genética , Adolescente , Osso e Ossos/diagnóstico por imagem , Síndrome de Camurati-Engelmann/metabolismo , Feminino , Humanos , Radiografia
20.
Metabolism ; 62(11): 1535-42, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23890519

RESUMO

Glucokinase (GCK) acts as a glucose sensor and stimulates the release of insulin from pancreatic ß-cells and any GCK gene mutations can lead to different forms of diabetes, such as GCK-monogenic diabetes of the young type 2 (MODY2), permanent neonatal diabetes and congenital hyperinsulinism. Many MODY2 causing mutations display a variation in the degree of severity, ranging from mild dietary-restricted forms to more detrimental presentation requiring insulin replacement. The present study reviews known and two novel GCK mutations in terms of molecular perturbation of the GCK atomic structure but also emphasizes the inactivating and activating properties of the GCK as treatment for T2DM. In silico analysis demonstrated that the newly discovered mutation p.Arg447Pro causes structural conformational changes that lead to the destabilization of the functional properties of the protein resulting in the reduction of glucose and MgATP2- affinity. The novel p.Glu440Stop nonsense mutation on the other hand inactivates the cytoplasmic enzymatic activity of the protein as it is responsible for the loss of the C-terminal end of the polypeptide that includes vital glucose-releasing residues. Based on the in silico models of existing structural data we identified several classes of GCK mutations and discuss their relation to disease outcome. GCK has a central role in controlling body glucose homeostasis and therefore is considered an outstanding drug target for developing new antidiabetic therapies using small molecular activators (GKAs). This study emphasizes the importance in understanding how inactivating and activating GCK mutations affect the mechanistic properties of this glucose sensor. Such information can become the basis for drug discovery of therapeutic compounds and the treatment of T2DM by targeting the GCK allosteric activator site.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucoquinase/genética , Glucoquinase/metabolismo , Hipoglicemiantes/uso terapêutico , Mutação , Arginina , Criança , Códon sem Sentido , Hiperinsulinismo Congênito/tratamento farmacológico , Diabetes Mellitus Tipo 2/enzimologia , Feminino , Glucoquinase/efeitos dos fármacos , Teste de Tolerância a Glucose , Ácido Glutâmico , Humanos , Hipoglicemiantes/farmacologia , Recém-Nascido , Prolina
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