RESUMO
Anauxetic dysplasia (AAD, OMIM 607095) is a rare skeletal dysplasia inherited as an autosomal recessive trait, which is caused by mutations in RMRP and allelic to a more common disorder, cartilage hair hypoplasia (CHH). CHH is a multi-system disorder with a variety of extraskeletal changes. Whereas AAD is a bone-restricted disorder with a more severe skeletal phenotype: affected individuals are extremely short and complicated by orthopedic morbidity, and the radiological changes include modification of the vertebral bodies and epiphyseal dysplasia of the hip, as well as generalized metaphyseal dysplasia and severe brachydactyly. Recently, genetic heterogeneity for AAD was proposed, because a familial case (two affected sibs) with an AAD-identical phenotype had compound heterozygous mutations in POP1, encoding a molecule functionally related to the gene product of RMRP. We report here a 5-year-old boy with the same phenotype born to a consanguineous couple. We identified a novel homozygous POP1 mutation (c.1744C>T, p.P582S) in the boy and the heterozygosity in the parents. It may be rational to coin the POP1-associated skeletal phenotype AAD type 2. © 2016 Wiley Periodicals, Inc.
Assuntos
Proteínas Reguladoras de Apoptose/genética , Nanismo/diagnóstico , Nanismo/genética , Estudos de Associação Genética , Mutação , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Fenótipo , Ribonucleoproteínas/genética , Alelos , Pré-Escolar , Biologia Computacional/métodos , Consanguinidade , Análise Mutacional de DNA , Éxons , Homozigoto , Humanos , Masculino , RadiografiaRESUMO
BACKGROUND: Amelogenesis imperfecta represents a group of developmental conditions, clinically and genetically heterogeneous, that affect the structure and clinical appearance of enamel. Amelogenesis imperfecta occurred as an isolated trait or as part of a genetic syndrome. Recently, disease-causing mutations in the FAM20A gene were identified, in families with an autosomal recessive syndrome associating amelogenesis imperfecta and gingival fibromatosis. CASE PRESENTATION: We report, the first description of a Moroccan patient with amelogenesis imperfecta and gingival fibromatosis, in whom we performed Sanger sequencing of the entire coding sequence of FAM20A and identified a homozygous mutation in the FAM20A gene (c.34_35delCT), already reported in a family with this syndrome. CONCLUSION: Our finding confirms that the mutations of FAM20A gene are causative for amelogenesis imperfecta and gingival fibromatosis and underlines the recurrent character of the c.34_35delCT in two different ethnic groups.
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Amelogênese Imperfeita/genética , Proteínas do Esmalte Dentário/genética , Fibromatose Gengival/genética , Deleção de Sequência/genética , Alanina/genética , Sequência de Bases , Criança , Códon sem Sentido/genética , Citosina , Éxons/genética , Feminino , Mutação da Fase de Leitura/genética , Hiperplasia Gengival/genética , Homozigoto , Humanos , Leucina/genética , Marrocos , Síndrome , TiminaRESUMO
BACKGROUND: Several pathogenesis and genetic factors influence predisposition to antituberculosis drug-induced hepatotoxicity (ATDH) especially for isoniazid (INH). However, the major susceptibility genes for ATDH are N-acetyltransferase 2 (NAT2) and cytochrome P450 2E1 (CYP2E1). NAT2 gene determines the individual's acetylator status (fast, intermediate or slow) to metabolize drugs and xenobiotics, while CYP2E1 c1/c1 genotype carriers had an increased risk of ATDH. Polymorphisms of the NAT2 and CYP2E1 genes vary remarkably among the populations of different ethnic origins. The aim of this study was to determine, for the first time, the frequency of slow acetylators in Moroccan population by genotyping of NAT2 gene variants and determining the genotype c1/c1 for CYP2E1 gene, in order to predict adverse effects of Tuberculosis treatment, particularly hepatotoxicity. RESULTS: The frequencies of specific NAT2 alleles were 53%, 25%, 2% and 4% for NAT2*5, NAT2*6, NAT2*7 and NAT2*14 respectively among 163 Moroccan studied group. Genotyping of CYP2E1 gene, by real-time polymerase chain reaction using TaqMan probes, revealed frequencies of 98.5% for c1/c1 and 1.5% for c1/c2 among 130 Moroccan studied group. CONCLUSION: The most prevalent genotypes of NAT2 gene in Moroccans are those which encode slow acetylation phenotype (72.39%), leading to a high risk of ATDH. Most Moroccans are homozygous for c1 allele of CYP2E1 gene which aggravates hepatotoxicity in slow acetylators. This genetic background should be taken into account in determining the minimum dose of INH needed to treat Moroccan TB patients, in order to decrease adverse effects.
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Arilamina N-Acetiltransferase/genética , Doença Hepática Induzida por Substâncias e Drogas/genética , Citocromo P-450 CYP2E1/genética , Antituberculosos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Frequência do Gene , Predisposição Genética para Doença , Humanos , Recém-Nascido , Isoniazida/efeitos adversos , Marrocos/epidemiologia , Polimorfismo de Nucleotídeo Único , Prevalência , Fatores de RiscoRESUMO
Noonan syndrome (NS; OMIM 163950) is an autosomal dominant RASopathy with variable clinical expression and genetic heterogeneity. Clinical manifestations include characteristic facial features, short stature, and cardiac anomalies. Variants in protein-tyrosine phosphatase, non-receptor-type 11 (PTPN11), encoding SHP-2, account for about half of NS patients, SOS1 in approximately 13%, RAF1 in 10%, and RIT1 each in 9%. Other genes have been reported to cause NS in less than 5% of cases including SHOC2, RASA2, LZTR1, SPRED2, SOS2, CBL, KRAS, NRAS, MRAS, PRAS, BRAF, PPP1CB, A2ML1, MAP2K1, and CDC42. Several additional genes associated with a Noonan syndrome-like phenotype have been identified. Clinical presentation and variants in patients with Noonan syndrome are this study's objectives. We performed Sanger sequencing of PTPN11 hotspot (exons 3, 8, and 13). We report molecular analysis of 61 patients with NS phenotype belonging to 58 families. We screened for hotspot variants (exons 3, 8, and 13) in PTPN11 gene by Sanger sequencing. Twenty-seven patients were carrying heterozygous pathogenic variants of PTPN11 gene with a similar frequency (41.4%) compared to the literature. Our findings expand the variant spectrum of Moroccan patients with NS phenotype in whom the analysis of hotspot variants showed a high frequency of exons 3 and 8. This screening test allowed us to establish a molecular diagnosis in almost half of the patients with a good benefit-cost ratio, with appropriate management and genetic counseling.
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Síndrome de Noonan , Proteína Tirosina Fosfatase não Receptora Tipo 11 , alfa-Macroglobulinas , Humanos , Éxons , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mutação , Síndrome de Noonan/genética , Síndrome de Noonan/diagnóstico , Síndrome de Noonan/patologia , Fenótipo , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteínas Ativadoras de ras GTPase/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genéticaRESUMO
Introduction: rheumatoid arthritis (RA) is a systemic autoimmune disease primarily affecting the joints. Arthritic disorders are associated with mutations of the Mediterranean fever (MEFV) gene. The aim of this study is to show whether MEFV mutations will be involved in the pathogenesis of RA, to explore the frequency of these mutations and to study the genotype-phenotype correlation between mutations in this gene and a cohort of Moroccan patients with rheumatoid arthritis (RA). Methods: the present study included 100 patients with RA and 200 control group (CG) who were unrelated individuals from the same ethnic. All patients were tested for auto-antibodies: cyclic citrullinated peptide (ACPA/anti-CCP2), rheumatoid factor (RF) and were analyzed by Sanger Sequencing of the 2 and 10 exons of MEFV gene (hot-spot according to the literature). Results: we detected 13 missense variants already MEFV gene mutation reported in the literature (S154T, G222A, G230L, L611H, L695A, M694V, I720M, A737L, P758S, L709A, T732A, G687A and P743L). Carrier rates of MEFV gene mutations were 24/100 (24%) for the RA group and 4/200 (4%) for CG. In the RA group, we observed that no man has presented with MEFV mutation. In the RA group, while gender, BMI, RF and ACPA were significantly higher in the mutation carrier group than those of the non-carrier group (p<0.01). The level of C-reactive protein and HAQ were slightly elevated in the carrier group but not significant. No other significant differences were observed between patients with MEFV mutations and those without MEFV mutations. Conclusion: the results of this study suggest that MEFV gene mutations appear to be an aggravating factor severity of RA and consequently, patients with RA might be screened for MEFV gene mutations in countries where FMF is frequent. We report also that our study is the first one in our country Morocco.
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Artrite Reumatoide , Artrite Reumatoide/genética , Genótipo , Humanos , Mutação , Fenótipo , Pirina/genética , Fator ReumatoideRESUMO
BACKGROUND: Merosin-deficient congenital muscular dystrophy type 1A (MDC1A) is a rare autosomal recessive genetic condition caused by deleterious mutations in the LAMA2 gene encoding the laminin-α2 chain. It is the most frequent subtype of congenital muscular dystrophies (CMDs) characterized by total laminin-α2 deficiency with muscle weakness at birth or in the first six months of life. To the best of our knowledge, this study reports the first molecular diagnosis and genetic defect of this heterogeneous form of CMD performed in a Moroccan medical genetic center using next-generation sequencing (NGS). It allows us to expand the mutational spectrum of the LAMA2 gene. CASE PRESENTATION: We report the case of a female Moroccan child with clinical and paraclinical features in favor of a CMD. She has global congenital hypotonia with generalized muscle weakness, psychomotor retardation, increased serum creatine kinase, and normal brain scan at the age of six months. Targeted NGS leads to the identification of a novel homozygous nonsense mutation c.2217G > A, p.(Trp739*) in the exon 16 of LAMA2. Sanger sequencing confirmed this mutation in the affected patient and showed that her parents are heterozygous carriers. CONCLUSIONS: A modern genetic analysis by NGS improves the genetic diagnosis pathway for adequate genetic counseling of affected families more precisely. An accession number from the National Center for Biotechnology Information (NCBI) ClinVar database was retrieved for this novel LAMA2 mutation.
Assuntos
Distrofias MuscularesRESUMO
A failure in optic fissure fusion during development can lead to blinding malformations of the eye. Here, we report a syndrome characterized by facial dysmorphism, colobomatous microphthalmia, ptosis and syndactyly with or without nephropathy, associated with homozygous frameshift mutations in FAT1. We show that Fat1 knockout mice and zebrafish embryos homozygous for truncating fat1a mutations exhibit completely penetrant coloboma, recapitulating the most consistent developmental defect observed in affected individuals. In human retinal pigment epithelium (RPE) cells, the primary site for the fusion of optic fissure margins, FAT1 is localized at earliest cell-cell junctions, consistent with a role in facilitating optic fissure fusion during vertebrate eye development. Our findings establish FAT1 as a gene with pleiotropic effects in human, in that frameshift mutations cause a severe multi-system disorder whereas recessive missense mutations had been previously associated with isolated glomerulotubular nephropathy.
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Blefaroptose/genética , Caderinas/genética , Coloboma/genética , Nefropatias/genética , Microftalmia/genética , Organogênese/genética , Sindactilia/genética , Adolescente , Adulto , Animais , Células Cultivadas , Criança , Pré-Escolar , Análise Mutacional de DNA , Embrião de Mamíferos , Olho/embriologia , Ossos Faciais/anormalidades , Feminino , Mutação da Fase de Leitura , Humanos , Junções Intercelulares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Cultura Primária de Células , Epitélio Pigmentado da Retina/citologia , Síndrome , Sequenciamento do Exoma , Adulto Jovem , Peixe-Zebra , Proteínas de Peixe-Zebra/genéticaRESUMO
BACKGROUND: Familial Mediterranean fever is an autoinflammatory disease of unknown etiology, characterized clinically by recurrent attacks of sudden-onset fever with arthralgia and/or thoracoabdominal pain and pathogenetically by autosomal recessive inheritance due to a mutation in the MEFV gene. Behçet's disease is an inflammatory disease characterized by recurrent oral and genital aphthous ulcerations, uveitis, and skin lesions. Preliminarily, our literature review suggested that patients with familial Mediterranean fever who also have Behçet's disease have only a single mutated familial Mediterranean fever gene. The MEFV gene mutation responsible for familial Mediterranean fever is probably a susceptibility factor for Behçet's disease, particularly for patients with vascular involvement, and both disorders can occur concurrently in a patient, as in the present case. CASE PRESENTATION: A 10-year-old girl of Moroccan origin presented to our institution for genetic consultation for genetic testing of the MEFV gene. She had fever associated with abdominal and diffuse joint pain in addition to headache. These symptoms have oriented pediatricians to familial Mediterranean fever. The evolution was marked by Behçet's syndrome symptoms. Sanger sequencing followed by complete exome sequencing analysis of the MEFV gene for the proband mutation revealed a novel variant. We conclude that the novel single variant c.2078 T > A (p.Met693Lys) could be responsible for the association of familial Mediterranean fever and Behçet's disease. CONCLUSION: To the best of our knowledge, this is the first report of a new variant in exon 10 of the MEFV gene in a Moroccan family. This novel variant should be listed in the MEFV sequence variant databases.
Assuntos
Síndrome de Behçet/genética , Febre Familiar do Mediterrâneo/genética , Predisposição Genética para Doença , Pirina/genética , Síndrome de Behçet/complicações , Criança , Febre Familiar do Mediterrâneo/complicações , Feminino , Humanos , Mutação , Sequenciamento do ExomaRESUMO
BACKGROUND: Xeroderma pigmentosum is an autosomal recessive inherited disease. The diagnosis is essentially based on clinical findings and the family history. This genodermatosis is genetically heterogeneous; to date, nine genes have been associated to this disorder. Based on the result of many studies, xeroderma pigmentosum complementation group C is the most common form of xeroderma pigmentosum. A founder mutation in the XPC gene was reported in the Maghreb region of northern Africa. According to these findings, the Department of Medical Genetics in Rabat offers molecular diagnosis by screening for the recurrent mutation c.1643_1644delTG which represents 74% of all the probands with xeroderma pigmentosum. CASE PRESENTATION: We describe the case of a 21-year-old Moroccan son of consanguineous parents diagnosed with xeroderma pigmentosum on the basis of sun-exposed skin abnormalities and bilateral ocular involvement. A molecular study led to the identification of a new frameshift insertion of four nucleotides in exon 9. CONCLUSIONS: To the best of our knowledge, this mutation has not been described. The sequencing of the ninth exon should be proposed as first line molecular analysis for all Moroccan patients with xeroderma pigmentosum.
Assuntos
População Negra , Análise Mutacional de DNA , Proteínas de Ligação a DNA/genética , Mutação da Fase de Leitura/genética , Predisposição Genética para Doença/genética , Xeroderma Pigmentoso/genética , Efeito Fundador , Predisposição Genética para Doença/epidemiologia , Humanos , Masculino , Marrocos , Prevalência , Xeroderma Pigmentoso/epidemiologia , Adulto JovemRESUMO
BACKGROUND: To date, a limited number of BRCA1/2 germline mutations have been reported in hereditary breast and/or ovarian cancer in the Moroccan population. Less than 20 different mutations of these two genes have been identified in Moroccan patients, and recently we reported a further BRCA2 mutation (c.1310_1313delAAGA; p.Lys437IlefsX22) in three unrelated patients, all from the North-East of the country. We aimed in this study to evaluate the frequency and geographic distribution of this BRCA2 frameshift mutation, in order to access its use as the first-line BRCA genetic testing strategy for Moroccan patients. We enrolled in this study 122 patients from different regions of Morocco, with suggestive inherited predisposition to breast and ovarian cancers. All subjects gave written informed consent to BRCA1/2 genetic testing. According to available resources of our lab and enrolled families, 51 patients were analyzed by the conventional individual exon-by-exon Sanger sequencing, 23 patients were able to benefit from a BRCA next generation sequencing and a target screening for exon 10 of BRCA2 gene was performed in 48 patients. RESULTS: Overall, and among the 122 patients analyzed for at least the exon 10 of the BRCA2 gene, the c.1310_1313delAAGA frameshift mutation was found in 14 patients. Genealogic investigation revealed that all carriers of this mutation shared the same geographic origin and were descendants of the North-East of Morocco. DISCUSSION: In this study, we highlighted that c.1310_1313delAAGA mutation of BRCA2 gene is recurrent with high frequency in patients from the North-East region of Morocco. Therefore, we propose to use, in public health strategies, the detection of this mutation as the first-line screening tests in patients with breast and ovarian cancer originated from this region.
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Proteína BRCA2/genética , Neoplasias da Mama/genética , Mutação da Fase de Leitura , Predisposição Genética para Doença/genética , Neoplasias Ovarianas/genética , Proteína BRCA1/genética , Neoplasias da Mama/prevenção & controle , Éxons/genética , Feminino , Frequência do Gene , Testes Genéticos , Geografia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Programas de Rastreamento , Marrocos , Neoplasias Ovarianas/prevenção & controleRESUMO
At present, breast cancer is the most common type of cancer in females. The majority of cases are sporadic, but 5-10% are due to an inherited predisposition to develop breast and ovarian cancers, which are transmitted as an autosomal dominant form with incomplete penetrance. The beneficial effects of clinical genetic testing, including next generation sequencing (NGS) for BRCA1/2 mutations, is major; in particular, it benefits the care of patients and the counseling of relatives that are at risk of breast cancer, in order to reduce breast cancer mortality. BRCA genetic testing was performed in 15 patients with breast cancer and a family with positivity for the heterozygous c.6428C>A mutation of the BRCA2 gene. Informed consent was obtained from all the subjects. Genomic DNAs were extracted and the NGS for genes was performed using the Ion Torrent Personal Genome Machine (PGM) with a 316 chip. The reads were aligned with the human reference HG19 genome to elucidate variants in the BRCA1 and BRCA2 genes. Mutations detected by the PGM platform were confirmed by target direct Sanger sequencing on a second patient DNA sample. In total, 4 BRCA variants were identified in 6 families by NGS. Of these, 3 mutations had been previously reported: c.2126insA of BRCA1, and c.1310_1313delAAGA and c.7235insG of BRCA2. The fourth variant, c.3453delT in BRCA1, has, to the best of our knowledge, never been previously reported. The present study is the first to apply NGS of the BRCA1 and BRCA2 genes to a Moroccan population, prompting additional investigation into local founder mutations and variant characteristics in the region. The variants with no clear clinical significance may present a diagnostic challenge when performing targeted resequencing. These results confirm that an NGS approach based on Ampliseq libraries and PGM sequencing is a highly efficient, speedy and high-throughput mutation detection method, which may be preferable in lower income countries.
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INTRODUCTION: Primary hyperoxaluria type 1 (PH1) is an autosomal recessive disorder caused by deficiency of alanine glyoxylate aminotransferase, due to a defect in the AGXT gene. Several mutations in this gene have been reported and some of them have been observed in multiple populations. The aim of our study was to analyze the mutations causing PH1 in the Moroccan population and to estimate its prevalence in Morocco. METHODS: Molecular studies of 29 unrelated Moroccan patients with PH were performed by direct sequencing of all exons of the AGXT gene. In addition, to estimate the prevalence of PH1, we screened for the recurrent p.Ile244Thr mutation in 250 unrelated Moroccan newborns using real-time polymerase chain reaction. RESULTS: Four pathogenic mutations were detected in 25 unrelated patients. The c.731T>C (p.Ile244Thr) was the most frequent mutation with a frequency of 84%. The other three mutations were c.33delC, c.976delG, and c.331C>T. The prevalence of the PH1 mutation among Moroccans was then estimated to range from 1/7267 to 1/6264. CONCLUSION: PH1 is one of the most prevalent genetic diseases in the Moroccan population and is probably underdiagnosed. Front line genetic testing for PH1 in Morocco should be initiated using an assay for the recurrent p.Ile244Thr mutation. This strategy would provide a useful tool for precocious diagnosis of presymptomatic individuals and to prevent their rapid progression to renal failure.
Assuntos
Hiperoxalúria Primária/genética , Transaminases/genética , Adolescente , Adulto , Alelos , Criança , Pré-Escolar , Éxons , Feminino , Testes Genéticos , Humanos , Hiperoxalúria Primária/diagnóstico , Hiperoxalúria Primária/epidemiologia , Lactente , Recém-Nascido , Masculino , Marrocos/epidemiologia , Mutação , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/métodosRESUMO
BACKGROUND: Breast cancer is the most common cancer in women worldwide. About 5 to 10% of cases are due to an inherited predisposition in two major genes, BRCA1 and BRCA2, transmitted as an autosomal dominant form. Male breast cancer is rare and is mainly due to BRCA2 than BRCA1 germline mutations. OBJECTIVE: Molecular study of BRCA2 gene in man with familial breast cancer. METHODS: PCR and direct sequencing of BRCA2 gene. RESULTS: Identification of novel heterozygous germline mutation c.6428C>A ; p.Ser2143Stop of BRCA2 gene.
Assuntos
Neoplasias da Mama Masculina/genética , Códon sem Sentido/genética , Genes BRCA2 , Predisposição Genética para Doença , Adulto , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Neoplasias da Mama Masculina/terapia , Análise Mutacional de DNA , Humanos , Masculino , Marrocos , Resultado do TratamentoRESUMO
BACKGROUND: Breast cancer is worldwide the most common cancer in women and is a major public health problem. Genes with high or low penetrance are now clearly implicated in the onset of breast cancer, mostly the BRCA genes. All women in families at high risk of breast cancer do not develop tumours, even when they carry the familial mutation, suggesting the existence of genetic and environmental protective factors. Several studies have shown that consanguinity is linked to a decreased or an increased risk of breast cancer, but to the best of our knowledge, there is no study concerning the association between consanguinity and the occurrence of tumours in women with high risk of breast cancer. The objective of this study was to examine whether parental consanguinity in families with genetic predisposition to breast cancer affect the risk of siblings for having this cancer. MATERIALS AND METHODS: Over a six-year period, 72 different patients with a histological diagnosis of breast or ovarian cancer from 42 families were recruited for genetic counselling to the Department of Medical Genetics, Rabat. Consanguinity rate was determined in cases and compared to the consanguinity rate in the Moroccan general population. RESULTS: Consanguinity rates were 9.72% in patients and 15.3% in controls, but the difference was statistically not significant (p>0.001) and the mean coefficient of consanguinity was lower in breast cancer patients (0.0034) than in controls (0.0065). CONCLUSIONS: Despite the relatively small sample size of the current study, our results suggest that parental consanguinity in Moroccan women might not be associated with an altered risk of breast cancer. Large scale studies should be carried out to confirm our results and to develop public health programs.
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Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Consanguinidade , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Família , Feminino , Aconselhamento Genético , Predisposição Genética para Doença , Humanos , Marrocos/epidemiologia , Risco , Fatores de RiscoRESUMO
Xeroderma pigmentosum (XP) is an autosomal recessive inherited disease which is genetically heterogeneous. The prevalence of this genodermatosis is estimated to be 1/1 000 000 in the USA; it is more common in Japan and probably in other populations with high levels of consanguinity. The molecular diagnosis and identification of mutation in patients requires the knowledge of the causative gene by the determination of XP complementation groups. Soufir et al. have reported that XPC is the major disease-causing gene with a recurrent mutation in the Mediterranean region. The mutation c.1643_1644delTG (p.Val548AlafsX25) represents alone 74% of all the XP probands tested and 87% in XP type C in North African patients with founder effect. We used molecular epidemiological methods in the present study to calculate the frequency of heterozygote for this mutation in Moroccan newborns and estimate the prevalence of XP in the Moroccan population. DNA extracted from umbilical cord blood samples of 250 newborns were tested for the recurrent XPC mutation c.1643_1644delTG using real-time polymerase chain reaction. Heterozygotes profiles were confirmed by direct sequencing. Among 250 newborns tested, one subject was heterozygous for the mutation c.1643_1644delTG. The carrier frequency was estimated to be 1/250 which would imply that the prevalence of XP would be approximately 1/80 504 considering the effect of consanguinity. This is the first report of the prevalence of XP in an Arab country and it shows that the prevalence of xeroderma pigmentosum is higher than that found in Europe and the USA.
Assuntos
Proteínas de Ligação a DNA/genética , Xeroderma Pigmentoso/epidemiologia , Xeroderma Pigmentoso/genética , Feminino , Efeito Fundador , Frequência do Gene , Heterozigoto , Humanos , Recém-Nascido , Masculino , Marrocos/epidemiologia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Deleção de SequênciaRESUMO
The cytochromes P450 are a superfamily of oxidative enzymes, which are implicated in the metabolism of a large number of endogenous substances as well as exogenous chemicals. The cytochrome P450 (CYP3A5) appears to play an important role in drug metabolism activity. The most frequent mutation in the CYP3A5 gene, affecting its activity, consists of a G6986A transition within intron 3. In this study, we determined the allelic frequency of CYP3A5*3 in a Moroccan population, consisting of 108 individuals including 10 renal transplant patients. About 8.33% (9/108) of the subjects were homozygous wild-type (CYP3A5*1/*1), 37.04% (40/108) were heterozygous (CYP3A5*1/*3), and 54.63% (59/108) were homozygous (CYP3A5*3/*3). Therefore, CYP3A5*3 variant was the most frequent allele detected at 73.15%. In the second part of this work, we assessed the influence of the CYP3A5 polymorphism on tacrolimus doses required for 10 renal transplant patients who are receiving tacrolimus as immunosuppressive therapy. Our results showed that, during the first 3 months after kidney transplantation, the tacrolimus daily requirements for heterozygous patients (CYP3A5*3/*1) were higher compared with homozygous patients (CYP3A5*3/*3) (0.133 ± 0.026 vs. 0.21 ± 0.037 mg/kg/day). After the third month the difference was also observed, whereby the mean of tacrolimus daily requirements for patients with CYP3A5*3/*3 and CYP3A5*1/*3 was 0.053 ± 0.013 and 0.08 ± 0.014 mg/kg/day, respectively. This first study in Morocco provides genetic data related to the frequency of genetic polymorphisms of CYP3A5 and opens the perspective to develop other pharmacogenetic studies.
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População Negra/genética , Citocromo P-450 CYP3A/genética , Frequência do Gene , Imunossupressores/administração & dosagem , Transplante de Rim/imunologia , Polimorfismo Genético , Tacrolimo/administração & dosagem , Adulto , Relação Dose-Resposta a Droga , Feminino , Heterozigoto , Homozigoto , Humanos , Imunossupressores/metabolismo , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Marrocos , Farmacogenética , Tacrolimo/metabolismo , Adulto JovemRESUMO
BACKGROUND: Epidemiological and experimental evidence support the role of host genetics in treatment response and viral clearance in chronic hepatitis C (CHC). Recently, the CC genotype of IL28B single-nucleotide polymorphism (SNP) rs12979860 has been associated with spontaneous viral clearance and a better treatment response. The distribution of this polymorphism varies according to populations. Frequency of rs12979860 SNP alleles in the Moroccan population is unknown. The aim of our study was to estimate the frequency of the C allele of this SNP in the Moroccan population and, in parallel, in a cohort of Moroccan patients with CHC treated with pegylated interferon-alpha and ribavirin. METHODS: We used real-time polymerase chain reaction assay based on TaqMan technology to determine the allele frequency of the rs12979860 SNP in 100 Moroccan newborn infants. We also compared the frequency of the CC genotype between two groups of patients with genotype 1-CHC treated by combination therapy: group1, n=30 patients, responders who achieved sustained viral response (SVR) and group2, n=30 patients, nonresponders. RESULTS: The rs12979860 C allele frequency was estimated to be 73% in the Moroccan population. The frequency of this allele in the group of patients with CHC was only 58.3%, and the CC genotype is more prevalent in group1 (62.5%) than in group 2. CONCLUSIONS: This is the first report providing genetic data related to the frequency of genetic polymorphisms of IL28B in Morocco. The C-allele frequency of the IL28B gene SNP rs12979860 in Morocco is higher than in the African populations. Distribution of this SNP distinguishes in a population of CHC between SVR and nonresponders. This result merits consideration and should be studied by analyzing a larger sample size of patients.
Assuntos
Alelos , Hepatite C Crônica/genética , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Adulto , Sequência de Bases , Estudos de Coortes , Primers do DNA , Hepatite C Crônica/tratamento farmacológico , Humanos , Recém-Nascido , Interferons , Marrocos , Reação em Cadeia da Polimerase em Tempo Real , Ribavirina/farmacologiaRESUMO
Germline mutations in the BRCA1 and BRCA2 genes highly predispose to breast and ovarian cancers and are responsible for a substantial proportion of familial breast and ovarian cancers. No female individuals from families from Morocco affected by breast cancer with mutations of these genes have previously been reported, and clinicians in Morocco are unaccustomed to dealing with healthy female individuals carrying mutations in the BRCA genes. This study aimed to report the initial experience of a group of Moroccan investigators carrying out predictive genetic testing to detect a known familial mutation in healthy Moroccan females with a high risk of developing breast cancer and to introduce supervision of these asymptomatic female carriers as a new approach in the prevention and early diagnosis of breast and ovarian cancers in Morocco. Presymptomatic diagnosis was carried out using DNA genetic testing in 5 healthy Moroccan female individuals from three families with an elevated risk of developing breast cancer. These are the first Moroccan families reported to be affected by breast cancers associated with BRCA mutations. Presymptomatic diagnosis was carried out for breast cancer in 5 female individuals from three Moroccan families with BRCA mutations. Two of the families are the first reported incidence of the founder mutation Ashkenazi BRCA1-185_186delAG in Moroccan patients. The third family carried the known BRCA2 mutation c.5073dupA/p.trp1692metfsX3. We tested the presence of these mutations in 5 asymptomatic healthy females from the three families. Two sisters from family 1 carried the BRCA1-185_186delAG mutation, whereas the third female individual from family 2 carried the c.5073dupA/p.trp1692metfsX3 mutation. However, one healthy female individual and her mother from family 3 did not carry the familial mutation of the BRCA1 gene. This study found BRCA mutations in three asymptomatic subjects, suggesting that this is the first step towards the development of persistent medical monitoring of females from families with a history of breast and ovarian cancers. Consequently, it is crucial for oncologists in Morocco to initiate the supervision of healthy female individuals with genetic defects which may lead to hereditary cancers.