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Cancer is a major health concern and accounts for one of the main causes of death worldwide. Innovative strategies are needed to aid in the diagnosis and treatment of different types of cancers. Recently, there has been an evolving interest in utilizing nanobodies of camel origin as therapeutic tools against cancer. Nanotechnology uses nanobodies an emerging attractive field that provides promises to researchers in advancing different scientific sectors including medicine and oncology. Nanobodies are characteristically small-sized biologics featured with the ability for deep tissue penetration and dissemination and harbour high stability at high pH and temperatures. The current review highlights the potential use of nanobodies that are naturally secreted in camels' biological fluids, both milk and urine, in the development of nanotechnology-based therapy for treating different typesQuery of cancers and other diseases. Moreover, the role of nano proteomics in the invention of novel therapeutic agents specifically used for cancer intervention is also illustrated.
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Objective: To evaluate COVID19 patients' clinical characteristics, risk factors, and COVID-19 severity at baseline and over one month following hospitalization. Design setting and participants: This prospective cohort study of 598 Saudi COVID19 patients recruited from 4 major medical institutions nationwide between June 01, 2020, and February 28, 2021. Patients were stratified into different demographic characteristics and COVID-19 severity scale. Results: Of the 598 hospitalized adult COVID19 patients (mean [range] age, 57 [46 to 65] years; 59% male), 300 (50.16%) had severe clinical COVID-19. Comorbidity was high among hospitalized patients (73.5 %), with diabetes mellitus (n=; 46%) and hypertension (n=; 41%) being the most common prevalent. In a multivariate logistic regression model, patient demographics and clinical factors such as age (odds ratio [OR], 1.014 per year; 95% CI, 1.003-1.025), male sex (OR, 1.63; 95% CI, 1.02-2.62), diabetes mellitus (OR, 1.63; 95% CI, 1.06-2.49), obesity (OR, 1.93; 95% CI, 1.26-2.94), oxygen saturation<92% (OR, 4.83; 95% CI, 2.96-7.86), and high neutrophil to lymphocyte ratio (OR, 3.74 per unit; 95% CI, 1.96-7.14) were independently associated with higher COVID-19 severity. Moreover, more than 60% of male patients and middle-aged patients (40-60 years) were associated with the use of COVID-19 medications, including favipiravir and dexamethasone, during their hospital stay. Additionally, the rate of invasive mechanical ventilation was the highest in female patients (61.5%) and in middle-aged patients (46.2%). However, the death rate was slightly higher in males (56%) than in female patients and in elderly patients (52%). In Cox proportional analysis, age associated with increased risk of 60-days mortality (Hazard ratio; HR, 1.05 per year; 95% CI, 1.018-1.098). Additionally, the Riyadh region associated with more COVID-19 cases required invasive respiratory support (57.7%) and Jeddah was associated with more deceased COVID-19 cases (44%). Conclusions: The data shows that comorbidity is associated with hospitalization among COVID-19 patients, which indicates the level of severity. Infection during the winter season (November), male gender, elderly, and those with pre-existing diabetes mellitus or obesity were associated with higher COVID-19 clinical severity.
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Objectives: There are limited data on the efficacy and safety of favipiravir antiviral in coronavirus disease 2019 (COVID-19), particularly in the more progressed disease phase. This study aims to evaluate the favipiravir effect on reducing the length of hospital stay and in-hospital mortality among moderate and severe hospitalized COVID-19 patients. Methods: A prospective, multicenter observational study was conducted that included moderate and severe hospitalized adult COVID-19 patients in four major regions (Riyadh (Riyadh), Eastern (Dammam), Al-Qassem (Buraydah), and Macca (Jeddah) of Saudi Arabia. For the primary outcome of all-cause mortality, a Cox proportional hazard analysis was performed. While the association between favipiravir use and length of hospital stay was determined using adjusted generalized linear model. This study was approved by the Central Institutional Review Board in The Saudi Ministry of Health (MoH) with the approval number IRB # 20-85-M. Results: This study included 598 moderate and severe COVID-19 patients, of whom 156 (26%) received favipiravir. Favipiravir treatment was associated with more extended hospital stays (14 vs. 10 median days, P = 0.034) and higher mortality rate (aHR 3.63; 95% CI 1.06-12.45) compared to no favipiravir regimen. Despite lack of effectiveness, favipiravir use was only associated with higher diarrhea adverse effects (12 vs. 5%, P = 0.002), but it did not affect the renal and liver profiles of patients. Conclusion: Favipiravir was ineffective in reducing the length of hospital stay and in-hospital mortality in patients with moderate and severe COVID-19.
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ABSTRACT: Prevalence of bleeding disorders vary due to several factors including geographical location. Mild bleeding disorders can lead to iron deficiency, morbidity, and in severe cases mortality. Quantification of haemorrhagic symptoms is a key component in management of bleeding disorders and a challenging task for clinicians.An abridged version of MCMDM-1vWD questionnaire with validated Arabic translation was used to quantify bleeding disorders in adult students (nâ=â1138) in 4 different regions of Kingdom of Saudi Arabia. Statistical analysis was performed to indicate gender disparity and prevalence.74.5% of respondents answered at least 1 question with affirmation, with 32.3% affected in Riyadh showing the highest prevalence and 14.03% affected in Dammam showing the least prevalence (P-valueâ<â.001). Gender-wise, higher prevalence of bleeding disorders in females 54.9% than in males 45.1% was observed (P-value .01). Epistaxis prevalence was significantly higher in males 30.7% vs 23.2% in females (P-value .0004), while cutaneous symptoms were reported significantly more by female participants 29.7% vs 12.3% in males (P-valueâ<â.001). Menorrhagia was reported by 28% of females, with heavy bleeding experienced by 57.6% female participants forâ<7âdays while in 42.4% of females for >7âdays.The current study signifies the ethnic distribution and gender disparity of mild bleeding disorders, and highlights the need for national surveillance system in order to improve management of patients with bleeding disorders.
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Hemorragia/epidemiologia , Adolescente , Adulto , Estudos Transversais , Epistaxe/epidemiologia , Feminino , Humanos , Masculino , Menorragia/epidemiologia , Prevalência , Arábia Saudita/epidemiologia , Índice de Gravidade de Doença , Fatores Sexuais , Estudantes de Medicina/estatística & dados numéricos , Adulto JovemRESUMO
Methylenetetrahydrofolate reductase (MTHFR) polymorphism plays a fundamental role in susceptibility to various diseases, including cancers and autoimmune diseases. In the current study, we aimed to compare genotype and allele frequency variations of rs1801131, one of the most common variants found in the MTHFR gene, among Saudi smokers and non-smokers. We hypothesized that genetic variations of this gene are responsible for many diseases, particularly those caused by cigarette smoking (CS) such as pulmonary diseases, oral cancer and lung cancer. We performed a case-control study on a sample of 235 healthy smokers and 239 healthy non-smokers in Saudi Arabia. The rs1801131 SNP genotypes were determined using a genotyping assay and multiple in silico algorithmic software programs were used to identify the effects and structural functions of the rs1801131 (Glu429Ala) mutation. Using chi-squared tests, we found that, among smokers, TG and GG genotype carriers had 0.209-fold (OR = 0.209, P < 0.005) and 0.427-fold (OR = 0.427, P = 0.003) lower risks of CS-related disease compared to TT reference genotypes. In addition, this protective effect was observed in Saudi smokers independent of age, gender, types of smoking, duration, and average daily smoking consumption. Filling a research gap by exploring this topic in the Saudi population, the current findings indicate that genotype and allele distributions of MTHFR rs1801131 polymorphism present fundamental protective effects against the risk of CS-related disease. These findings should be verified in future studies with larger sample sizes, different ethnicities, and patients suffering from CS-related diseases, such as oral cancer and lung cancer.
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Cigarette smoking is a major lifestyle factor leading to different human diseases. The DNA repair gene, thymine DNA glycosylase, is important to cell survival because it stops cells from becoming cancerous protecting/preventing DNA. Exposure to CS may induce genetic changes such as single nucleotide polymorphisms in DNA repair genes. Therefore, the purpose of this study was to investigate the genotype and allele distributions of four TDG SNPs with only smoking behavior in normal patients. Four TDG SNPs-rs4135066 (C/T), rs3751209 (A/G), rs1866074 (C/T), and rs1882018 (C/T) were analyzed by genotyping 235 and 239 blood samples collected from cigarette smokers and non-smokers, among the Saudi population. The results showed that TDG rs4135066 has a significant susceptibility effect observed in long-term smokers (>5 years; OR = 4.53; P = 0.0347) but not in short-term smokers (≤5 years) in contrast with non-smokers. Also, in smokers aged less than 29 years, the "CT," "TT," and "CT + TT" alleles of rs1882018 increased the risk of developing all diseases related to smoking by approximately 6, 4, and 5 times, respectively, in contrast with the ancestral "CC" homozygous allele. A comparison of the allele distributions of TDG SNPs in a Saudi population with those in other populations represented in the HapMap project showed that the genetic makeup of the Saudi Arabian population appears to differ from that of other ethnicities. Exceptions include the Yoruba people in Ibadan, Nigeria; those of Mexican ancestry in Los Angeles, California; the Luhya population in Webuye, Kenya; Gujarati Indians in Houston, Texas; and the Tuscan population in Italy, which showed similar allelic frequencies for rs3751209 compared to our Saudi population. In this ethnic, we have found a high variation in the distribution of the alleles and genotype frequencies on TDG gene. This variation on TDG SNP's with smoking could lead to increase the susceptibility to many diseases related to smoking habits in this population.
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Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Fumar/genética , Timina DNA Glicosilase/genética , Adulto , Alelos , Etnicidade/genética , Feminino , Frequência do Gene/genética , Genótipo , Humanos , MasculinoRESUMO
Sick sinus syndrome (SSS) is a group of disorders characterized by an abnormal cardiac impulse formation or propagation from the sinoatrial node. Mutated SCN5A has been reported in SSS, however, homozygosity of SCN5A is exceedingly rare. Here, we report a consanguineous family with four affected children with SSS. Symptomatic bradycardia necessitated implanting a pacemaker in all of them. Sequencing SCN5A revealed a novel homozygous variant (p.Cys1850Arg), which was predicted to interfere with protein folding. Our report describes the phenotype of a novel homozygous SCN5A variant and contributes to the compendium of molecular pathology of inherited arrhythmias in consanguineous populations.
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Mutação , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Síndrome do Nó Sinusal/genética , Adolescente , Feminino , Homozigoto , Humanos , Lactente , Masculino , Marca-Passo Artificial , Linhagem , Síndrome do Nó Sinusal/terapia , Adulto JovemRESUMO
Mutant alleles of CDH23, a gene that encodes a putative calcium-dependent cell-adhesion glycoprotein with multiple cadherin-like domains, are responsible for both recessive DFNB12 nonsyndromic hearing loss (NSHL) and Usher syndrome 1D (USH1D). The encoded protein cadherin 23 (CDH23) plays a vital role in maintaining normal cochlear and retinal function. The present study's objective was to elucidate the role of DFNB12 allelic variants of CDH23 in Saudi Arabian patients. Four affected offspring of a consanguineous family with autosomal recessive moderate to profound NSHL without any vestibular or retinal dysfunction were investigated for molecular exploration of genes implicated in hearing impairment. Parallel to this study, we illustrate some possible pitfalls that resulted from unexpected allelic heterogeneity during homozygosity mapping due to identifying a shared homozygous region unrelated to the disease locus. Compound heterozygous missense variants (p.(Asp918Asn); p.(Val1670Asp)) in CDH23 were identified in affected patients by exome sequencing. Both the identified missense variants resulted in a substitution of the conserved residues and evaluation by multiple in silico tools predicted their pathogenicity and variable disruption of CDH23 domains. Three-dimensional structure analysis of human CDH23 confirmed that the residue Asp918 is located at a highly conserved DXD peptide motif and is directly involved in "Ca2+" ion contact. In conclusion, our study identifies pathogenic CDH23 variants responsible for isolated moderate to profound NSHL in Saudi patients and further highlights the associated phenotypic variability with a genotypic hierarchy of CDH23 mutations. The current investigation also supports the application of molecular testing in the clinical diagnosis and genetic counseling of hearing loss.
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Caderinas/genética , Surdez/genética , Adolescente , Adulto , Alelos , Proteínas Relacionadas a Caderinas , Caderinas/metabolismo , Surdez/fisiopatologia , Família , Feminino , Frequência do Gene/genética , Genótipo , Humanos , Masculino , Mutação/genética , Mutação de Sentido Incorreto/genética , Linhagem , Retinose Pigmentar/genética , Arábia Saudita , Síndromes de Usher/genética , Sequenciamento do Exoma/métodosRESUMO
BACKGROUND: The one-stage assay is the most common method to measure factor VIII activity (FVIII : C) in hemophilia A patients. The chromogenic assay is another two-stage test involving purified coagulation factors followed by factor Xa-specific chromogenic substrate. AIM: This study aimed to assess the discrepancy and correlation between the chromogenic and one-stage assays in measuring FVIII : C levels in hemophilia patients receiving Extended Half-Life Elocta® as a recombinant extended half-life coagulation factor. METHODS: We performed a study comparing the measurements of FVIII : C levels by the chromogenic versus the one-stage assays at different drug levels. Data of FVIII : C levels, dosage, and the time interval from administration to measurement were retrieved from the hospital records. The correlation, mean differences, and discrepancy between the two assays were calculated. The linear regression analysis was used to predict the time interval till reaching 1% FVIII : C. RESULTS: Fourteen patients with 56 samples were included in the study. Of them, 13 patients were receiving Elocta® as a prophylactic, while one was receiving Elocta® on demand. One-third of these samples showed a discrepancy between the chromogenic and one-stage assays. The two assays were well correlated. Mean differences were significant at the individual and the time interval level. The time since the last Elocta® injection could significantly predict FVIII : C levels (ß = 0.366, P < 0.001). CONCLUSION: Our findings suggested a significant difference between both methods; the FVIII : C levels measured by the one-stage assay were less than those estimated by the chromogenic assay. However, the measurements of FVIII levels by the two assays were well correlated but discrepant in one-third of the samples. The levels of FVIII : C reach 1% after 5.4 days since the last Elocta® administration.
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Hearing loss (HL) is the most common sensory disorder worldwide and genetic factors contribute to approximately half of congenital HL cases. HL is subject to extensive genetic heterogeneity, rendering molecular diagnosis difficult. Mutations of the transmembrane channel-like 1 (TMC1) gene cause hearing defects in humans and mice. The precise function of TMC1 protein in the inner ear is unknown, although it is predicted to be involved in functional maturation of cochlear hair cells. TMC1 mutations result in autosomal recessive (DFNB7/11) and sometimes dominant (DFNA36) nonsyndromic HL. Mutations in TMC1 are responsible for a significant portion of HL, particularly in consanguineous populations. To evaluate the importance of TMC1 mutations in the Saudi population, we used a combination of autozygome-guided candidate gene mutation analysis and targeted next generation sequencing in 366 families with HL previously shown to lack mutations in GJB2. We identified 12 families that carried five causative TMC1 mutations; including three novel (c.362+3A > G; c.758C > T [p.Ser253Phe]; c.1396_1398delACC [p.Asn466del]) and two reported mutations (c.100C > T [p.Arg34Ter]; c.1714G > A [p.Asp572Asn]). Each of the identified recessive mutation was classified as severe, by both age of onset and severity of HL. Similarly, consistent with the previously reported dominant variant p.Asp572Asn, the HL phenotype was progressive. Eight families in our cohort were found to share the pathogenic p.Arg34Ter mutation and linkage disequilibrium was observed between p.Arg34Ter and SNPs investigated. Our results indicate that TMC1 mutations account for about 3.3% (12/366) of Saudi HL cases and that the recurrent TMC1 mutation p.Arg34Ter is likely to be a founder mutation.
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Perda Auditiva Neurossensorial/genética , Proteínas de Membrana/genética , Mutação , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Análise Mutacional de DNA , Orelha Interna/metabolismo , Éxons , Saúde da Família , Feminino , Ligação Genética , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , Arábia Saudita , Adulto JovemRESUMO
BACKGROUND: BRCA1/2 pathogenic variants have become associated with familial breast and ovarian cancers, and hereditary cancer-predisposition syndrome. With advances in molecular biology, BRCA profiling facilitates early diagnosis and the implementation of preventive and therapeutic strategies. The genes exhibit variable prevalence among different individuals and moderate interpretation complexity. BRCA deficiency is instrumental in cancer development, affects therapeutic options and is instrumental in drug resistance. In addition, BRCA1/2 profile is diverse across different groups and has been associated with the "founder effect" in certain populations. METHODS: In this review, we aim to detail the spectrum of BRCA1/2 variants and their associated risk estimates. RESULTS: The relationship between BRCA1/2 and hereditary and familial cancers is indisputable, yet BRCA screening methods are beset with limitations and lack clinical confidence. CONCLUSION: This review emphasizes the importance of screening BRCA genetics, in addition to their clinical utility. Furthermore, founder variants are anticipated in the Saudi population.
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Proteína BRCA1/genética , Proteína BRCA1/fisiologia , Proteína BRCA2/genética , Proteína BRCA2/fisiologia , Neoplasias da Mama/genética , Neoplasias Ovarianas/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Carcinogênese/genética , Detecção Precoce de Câncer , Feminino , Efeito Fundador , Perfilação da Expressão Gênica , Predisposição Genética para Doença/genética , Humanos , Epidemiologia Molecular , Síndromes Neoplásicas Hereditárias/genética , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/terapia , Arábia SauditaRESUMO
Coagulation factor V plays a significant role in the blood coagulation cascade as part of the prothrombinase complex. Factor V deficiency (FVD) is a rare autosomal recessive bleeding disorder with a variable phenotypic expression which varies from being asymptomatic-to-severe bleeding episodes. The aim of this study was to perform molecular and clinical characterization of FVD in patients originating from Saudi Arabia. Eleven patients (two males and nine females) with confirmed FVD were recruited in the study with ages ranging between 5 and 53 years. A next-generation sequencing-based hematology panel encompassing 393 known genes was used. A total of six sequence variations in F5 gene were identified, including four missense mutations (p.Pro189Leu, p.Trp2004Arg, p.Met2148Thr, p. Arg2202Cys), a deletion (p.Arg872Lysfs*12) and a splicing variant (c.1118+5G>T). Four variants were identified for the first time in this study. Three patients were homozygous for their respective mutations and seven patients were heterozygous. We were not able to identify a pathogenic variant in one patient of the cohort. In-silico and three-dimensional structural analyses were performed to predict the possible impact and functional consequences of the identified variants. To our knowledge, this is the first study addressing factor V mutations in patients with Arab ancestry. Results have helped in providing a definitive diagnosis to the patients and carrier detection in extended family members. Overall, the hematology panel assay was an efficient platform, demonstrating a formidable approach for the molecular diagnosis of other suspected bleeding disorders.
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Deficiência do Fator V/genética , Fator V/genética , Adolescente , Adulto , Sequência de Bases , Criança , Pré-Escolar , Deficiência do Fator V/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Mutação de Sentido Incorreto , Conformação Proteica , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Arábia Saudita/epidemiologia , Deleção de Sequência , Adulto JovemRESUMO
BACKGROUND: Inflammation is a fundamental factor that contributes to the development and progression of several types of cancer including colon cancer. Toll-like receptors (TLRs) and their signaling pathways have been reported to be associated with chronic inflammation and thereby induced cancer. Our aim was to investigate the expression and polymorphisms of TLR2 and their association with colon cancer. METHODS: Real-time PCR and immunohistochemistry were used to investigate TLR2 gene expression and to evaluate the potential risk of predisposition to colon cancer caused by three tagging single-nucleotide polymorphisms (SNPs) on TLR2, including rs3804100, rs4696480, and rs3804099. TaqMan assay was conducted on samples from 115 patients with colon cancer and 102 age- and sex-matched normal individuals. RESULTS: We found that, TLR2 was highly expressed in epithelial colon cancer cells and both TLR2 mRNA and protein levels, and significantly decreased in tumor tissues compared to normal tissues. Two of three TLR2 SNPs increased the risk of colon cancer. However, TLR2 rs3804099 increased the risk of colon cancer development by more than 3.8- and 5-fold in female patients and patients aged less than 57 years, respectively. The T allele of TLR2 rs3804100 showed a significant association with patients less than 57 years. In silico analysis of the TLR2 nucleotide substitution in SNP rs3804100 and rs3804099 determined that 67% and 70% probability of these single nucleotide variants alter splicing phenotypes, rs3804100 more specifically result on activating an additional splice site. Genotype and allele frequencies of rs4696480 were similar between the overall study populations. Thus, TLR2 rs4696480 appear to be not involved in colon cancer in our study population. CONCLUSIONS: There was a significant link between innate immunity deregulation through disruption of the TLRs and potential development of colon cancer. These SNPs can be used as screening markers for predicting colon cancer risk earlier in life to implement necessary prevention.
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Combined immunodeficiencies are a heterogeneous collection of primary immune disorders that exhibit defects in T cell development or function, along with impaired B cell activity even in light of normal B cell maturation. CARMIL2 (RLTPR) is a protein involved in cytoskeletal organization and cell migration, which also plays a role in CD28 co-signaling of T cells. Mutations in this protein have recently been reported to cause a novel primary immunodeficiency disorder with variable phenotypic presentations. Here, we describe seven patients from three unrelated, consanguineous multiplex families that presented with dermatitis, esophagitis, and recurrent skin and chest infections with evidence of combined immunodeficiency. Through the use of whole exome sequencing and autozygome-guided analysis, we uncovered two mutations not previously reported (p.R50T and p.L846Sfs) in CARMIL2. Real-time PCR analysis revealed that the biallelic frameshift mutation is under negative selection, likely due to nonsense-mediated RNA decay and leading to loss of detectable protein upon immunoblotting. Protein loss was also observed for the missense mutation, and 3D modeling suggested a disturbance in structural stability due to an increase in the electrostatic energy for the affected amino acid and surrounding residues. Immunophenotyping revealed that patient Treg counts were significantly depressed, and that CD4+ T cells were heavily skewed towards the naïve status. CD3/CD28 signaling impairment was evidenced by reduced proliferative response to stimulation. This work broadens the allelic heterogeneity associated with CARMIL2 and highlights a deleterious missense alteration located outside the leucine-rich repeat of the protein, where all other missense mutations have been reported to date.
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Dermatite/genética , Esofagite/imunologia , Síndromes de Imunodeficiência/genética , Proteínas dos Microfilamentos/imunologia , Infecções Respiratórias/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Dermatite/imunologia , Esofagite/genética , Feminino , Humanos , Síndromes de Imunodeficiência/imunologia , Masculino , Proteínas dos Microfilamentos/genética , Mutação , Linhagem , Infecções Respiratórias/genética , Arábia Saudita , Sequenciamento do ExomaRESUMO
BACKGROUND/AIMS: Laron syndrome (LS) is an autosomal recessive disease characterized by marked short stature and very low serum IGF-1 and IGFBP-3 levels. This study assessed the clinical and endocrine features alongside determining the growth hormone receptor gene (GHR) mutation in Saudi Arabian patients with LS in order to establish whether or not a genotype/phenotype correlation is evident in this large cohort. SUBJECTS AND METHODS: A total of 40 Saudi Arabian patients with a suspected diagnosis of LS were recruited and subjected to a full clinical and endocrine investigation together with direct sequencing of the coding regions of the GHR gene. RESULTS: GHR mutations were identified in 34 patients from 22 separate nuclear families. All 34 molecularly confirmed patients had the typical clinical and endocrinological manifestations of LS. Eleven different mutations (9 previously unreported) were detected in this cohort of patients, all inherited in an autosomal recessive homozygous form. No genotype/phenotype correlation was apparent. CONCLUSION: The identification of pathogenic mutations causing LS will be of tremendous use for the molecular diagnosis of patients in Saudi Arabia and the region in general, with respect to prevention of this disease in the forms of future carrier testing, prenatal testing, premarital screening and preimplantation genetic diagnosis.
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Hormônio do Crescimento Humano/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Síndrome de Laron/genética , Mutação , Receptores da Somatotropina/genética , Estatura/genética , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Humanos , Lactente , Síndrome de Laron/metabolismo , Masculino , Receptores da Somatotropina/metabolismo , Arábia SauditaRESUMO
Maple syrup urine disease (MSUD), an autosomal recessive inborn error of metabolism due to defects in the branched-chain α-ketoacid dehydrogenase (BCKD) complex, is commonly observed among other inherited metabolic disorders in the kingdom of Saudi Arabia. This report presents the results of mutation analysis of three of the four genes encoding the BCKD complex in 52 biochemically diagnosed MSUD patients originating from Saudi Arabia. The 25 mutations (20 novel) detected spanned across the entire coding regions of the BCKHDA, BCKDHB and DBT genes. There were no mutations found in the DLD gene in this cohort of patients. Prediction effects, conservation and modelling of novel mutations demonstrated that all were predicted to be disease-causing. All mutations presented in a homozygous form and we did not detect the presence of a "founder" mutation in any of three genes. In addition, prenatal molecular genetic testing was successfully carried out on chorionic villus samples or amniocenteses in 10 expectant mothers with affected children with MSUD, molecularly characterized by this study.
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MOTIVATION: High-throughput sequencing platforms are increasingly used to screen patients with genetic disease for pathogenic mutations, but prediction of the effects of mutations remains challenging. Previously we developed SAAPdap (Single Amino Acid Polymorphism Data Analysis Pipeline) and SAAPpred (Single Amino Acid Polymorphism Predictor) that use a combination of rule-based structural measures to predict whether a missense genetic variant is pathogenic. Here we investigate whether the same methodology can be used to develop a differential phenotype predictor, which, once a mutation has been predicted as pathogenic, is able to distinguish between phenotypes-in this case the two major clinical phenotypes (hypertrophic cardiomyopathy, HCM and dilated cardiomyopathy, DCM) associated with mutations in the beta-myosin heavy chain (MYH7) gene product (Myosin-7). RESULTS: A random forest predictor trained on rule-based structural analyses together with structural clustering data gave a Matthews' correlation coefficient (MCC) of 0.53 (accuracy, 75%). A post hoc removal of machine learning models that performed particularly badly, increased the performance (MCC = 0.61, Acc = 79%). This proof of concept suggests that methods used for pathogenicity prediction can be extended for use in differential phenotype prediction. AVAILABILITY AND IMPLEMENTATION: Analyses were implemented in Perl and C and used the Java-based Weka machine learning environment. Please contact the authors for availability. CONTACTS: andrew@bioinf.org.uk or andrew.martin@ucl.ac.uk SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Mutação , Cadeias Pesadas de Miosina , Cardiomiopatias/genética , Cardiomiopatias/fisiopatologia , Análise por Conglomerados , Humanos , Miosinas VentricularesRESUMO
BACKGROUND: Understanding and predicting the effects of mutations on protein structure and phenotype is an increasingly important area. Genes for many genetically linked diseases are now routinely sequenced in the clinic. Previously we focused on understanding the structural effects of mutations, creating the SAAPdb resource. RESULTS: We have updated SAAPdb to include 41% more SNPs and 36% more PDs. Introducing a hydrophobic residue on the surface, or a hydrophilic residue in the core, no longer shows significant differences between SNPs and PDs. We have improved some of the analyses significantly enhancing the analysis of clashes and of mutations to-proline and from-glycine. A new web interface has been developed allowing users to analyze their own mutations. Finally we have developed a machine learning method which gives a cross-validated accuracy of 0.846, considerably out-performing well known methods including SIFT and PolyPhen2 which give accuracies between 0.690 and 0.785. CONCLUSIONS: We have updated SAAPdb and improved its analyses, but with the increasing rate with which mutation data are generated, we have created a new analysis pipeline and web interface. Results of machine learning using the structural analysis results to predict pathogenicity considerably outperform other methods.
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Biologia Computacional/métodos , Doenças Genéticas Inatas/genética , Mutação/genética , Fenótipo , Conformação Proteica , Proteínas/genética , Software , Substituição de Aminoácidos/genética , Inteligência Artificial , Humanos , Internet , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
OBJECTIVE: To investigate the protective role of Cardiospermum halicacabum (C. halicacabum) leaf extract on glycoprotein metabolism in streptozotocin (STZ)-induced diabetic rats. METHODS: Diabetes was induced in male albino Wistar rats by intraperitonial administration of STZ. The C. halicacabum leaf extract (CHE) was administered orally to normal and STZ-diabetic rats for 45 days. The effects of C. halicacabum leaf extract (CHE) on plasma and tissue glycoproteins (hexose, hexosamine, fucose and sialic acid) were determined. RESULTS: The levels of plasma and tissues glycoproteins containing hexose, hexosamine and fucose were significantly increased in STZ-induced diabetic rats. In addition, the level of sialic acid significantly increased in plasma and liver while decreased in kidney of STZ-induced diabetic rats. After administration of CHE to diabetic rats, the metabolic alteration of glycoprotein reverted towards normal levels. CONCLUSIONS: The present study indicates that the CHE possesses a protective effect on abnormal glycoprotein metabolism in addition to its antihyperglycemic activity.