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1.
Mamm Genome ; 35(3): 445-460, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38965090

RESUMO

The demographic history of human populations in North Africa has been characterized by complex migration processes that have determined the current genetic structure of these populations. We examined the autosomal markers of eight sampled populations in northern Africa (Tunisia and Libya) to explore their genetic structure and to place them in a global context. We genotyped a set of 30 autosomal single-nucleotide polymorphisms (SNPs) extending 9.5 Mb and encompassing the 17q21 inversion region. Our data include 403 individuals from Tunisia and Libya. To put our populations in the global context, we analyzed our data in comparison with other populations, including those of the 1000 Genomes Project. To evaluate the data, we conducted genetic diversity, principal component, STRUCTURE, and haplotype analyses. The analysis of genetic composition revealed the genetic heterogeneity of North African populations. The principal component and STRUCTURE analyses converged and revealed the intermediate position of North Africans between Europeans and Asians. Haplotypic analysis demonstrated that the normal (H1) and inverted (H2) polymorphisms in the chromosome 17q21 region occur in North Africa at frequencies similar to those found in European and Southwest Asian populations. The results highlight the complex demographic history of North Africa, reflecting the influence of genetic flow from Europe and the Near East that dates to the prehistoric period. These gene flows added to demographic factors (inbreeding, endogamy), natural factors (topography, Sahara), and cultural factors that play a role in the emergence of the diverse and heterogeneous genetic structures of North African populations. This study contributes to a better understanding of the complex structure of North African populations.


Assuntos
Cromossomos Humanos Par 17 , Variação Genética , Genética Populacional , Haplótipos , Polimorfismo de Nucleotídeo Único , Humanos , Cromossomos Humanos Par 17/genética , África do Norte , População Negra/genética , Tunísia , Análise de Componente Principal , Líbia , Frequência do Gene , População do Norte da África
2.
Mol Biol Rep ; 49(2): 1233-1258, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34854013

RESUMO

BACKGOUND: Bladder cancer (BCa) is a heterogeneous disease caused by the interaction between environmental and genetic risk factors. The goal of this case-control study was to evaluate the implication of a selected SNP panel in the risk of BCa development in a Tunisian cohort. We were also interested in studying the interaction between this predictive panel and environmental risk factors. METHODS: The case/control cohort was composed with 249 BCa cases and 255 controls. The designed Bladder cancer hereditary panel (BCHP) was composed of 139 selected variants. These variants were genotyped by an amplification-based targeted Next-Generation Sequencing (NGS) on the Ion Torrent Proton sequencer (Life Technologies, Ion Torrent technology). RESULTS: We have found that rs162555, rs2228000, rs10936599, rs710521, rs3752645, rs804276, rs4639, rs4881400 and rs288980 were significantly associated with decreased risk of bladder cancer. However the homozygous genotypes for VPS37C (rs7104333, A/A), MPG (rs1013358, C/C) genes or the heterozygous genotype for ARNT gene (rs1889740, rs2228099, rs2256355, rs2864873), GSTA4 (rs17614751) and APOBR/IL27 (rs17855750) were significantly associated with increased risk of bladder cancer development compared to reference group (OR 2.53, 2.34, 1.99, 2.00, 2.00, 1.47, 1.96 and 2.27 respectively). We have also found that non-smokers patients harboring heterozygous genotypes for ARNT/rs2864873 (A > G), ARNT/ rs1889740 (C > T) or GSTA4/rs17614751 (G-A) were respectively at 2.775, 3.069 and 6.608-fold increased risk of Bca development compared to non-smokers controls with wild genotypes. Moreover the ARNT CT (rs1889740), ARNT CG (rs2228099), ARNT TC (rs2864873) and GSS GA genotypes were associated with an increased risk of BCa even in absence of professional risk factors. Finally the decision-tree analysis produced a three major BCa classes. These three classes were essentially characterized by an intensity of tobacco use more than 20 pack years (PY) and the CYP1A2 (rs762551) genotype. CONCLUSIONS: The determined association between environmental factors, genetic variations and the risk of Bca development may provide additional information to urologists that may help them for clinical assessment and treatment decisions. Nevertheless, the underlying mechanisms through which these genes or SNPs affect the clinical behavior of BCas require further studies.


Assuntos
Transcriptoma/genética , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Tunísia/epidemiologia , Bexiga Urinária/patologia
3.
Mol Biol Rep ; 49(3): 1687-1700, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34854014

RESUMO

BACKGROUND: Alzheimer's disease (AD) is the most common neurodegenerative disorder in humans and presents a major health problem throughout the world. The etiology of AD is complex, and many factors are implicated, including mitochondria. Mitochondrial alteration has been proposed as a possible cause of AD. Therefore, several studies have focused on finding an association between inherited mitochondrial DNA variants and AD onset. METHODS: In this study, we looked, for the first time, for a potential association between mitochondrial haplogroups or polymorphisms and AD in the Tunisian population. We also evaluated the distribution of the major genetic risk factor for AD, the apolipoprotein E epsilon 4 (APOE ε4), in this population. In total, 159 single-nucleotide polymorphisms (SNPs) of mitochondrial DNA haplogroups were genotyped in 254 individuals (58 patients and 196 controls). An additional genotyping of APOE ε4 was performed. RESULTS: No significant association between mitochondrial haplogroups and AD was found. However, two individual SNPs, A5656G (p = 0.03821, OR = 10.46) and A13759G (p = 0.03719, OR = 10.78), showed a significant association with AD. APOE 4 was confirmed as a risk factor for AD (p = 0.000014). CONCLUSION: Our findings may confirm the absence of a relation between mitochondrial haplogroups and AD and support the possible involvement of some inherited variants in the pathogenicity of AD.


Assuntos
Doença de Alzheimer , DNA Mitocondrial , Alelos , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Estudos de Casos e Controles , DNA Mitocondrial/genética , Predisposição Genética para Doença , Genótipo , Humanos , Mitocôndrias/genética , Polimorfismo de Nucleotídeo Único/genética , Tunísia/epidemiologia
4.
J Clin Lab Anal ; 36(1): e24129, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34799866

RESUMO

BACKGROUND: Angiotensin-converting enzyme (ACE) plays a pivotal role in several pathologies including cancers. The association of insertion/deletion (I/D) polymorphism of the ACE gene with prostate cancer (PC) risk remains controversial. We aimed to investigate for the first time, to our Knowledge, in North Africa the potential relationship between ACE I/D polymorphism with PC susceptibility and clinical outcomes of PC patients. METHODS: This case-control study included 143 healthy individuals and 124 patients diagnosed with PC. Using genomic DNA, the samples were genotyped for ACE I/D polymorphism by polymerase chain reaction (PCR). RESULTS: We found that The D allele is significantly associated with an increased risk of PC and D/D + D/I genotypes were at 3 times increased risk of PC ([p = 0.005], OR = 2.95, IC 95% = 1.26-7.09) compared with I/I genotype (p = 0.003, OR = 0.3, IC 95% = 0.12-0.74). We observed an association between D/D and D/I genotypes with advanced age (≥70 years) (p = 0.014; r2  = 0.22). Furthermore, there is a significant prediction of advanced Gleason score ≥8 based on epidemiological parameters and ACE genotype (p = 0.000; R2  = 0.349), although no significant association was observed with stage and metastasis. CONCLUSION: The ACE I/D polymorphism is likely to predispose to PC and could play a role in PC progression and aggressiveness.


Assuntos
Predisposição Genética para Doença , Mutação INDEL/genética , Peptidil Dipeptidase A/genética , Neoplasias da Próstata , Idoso , Idoso de 80 Anos ou mais , Elementos Alu/genética , Estudos de Casos e Controles , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética , Tunísia
5.
Hum Biol ; 93(3): 163-177, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-37733614

RESUMO

The TAS2R38 gene is involved in bitter taste perception. This study documents the distinctive diversity patterns in northern Africa of functional single-nucleotide polymorphisms (SNPs) rs713598 and rs1726866 at the TAS2R38 locus and places those patterns in the context of global TAS2R38 diversity. Data previously genotyped with TaqMan assay were analyzed for rs713598 and rs1726866 for 375 unrelated subjects (305 Tunisians from seven locations: Mahdia, Sousse, Kesra, Nebeur, Kairouan, Smar, and Kerkennah; plus 70 Libyans). Data were analyzed to present haplotypes and genotypes before comparison with data from worldwide populations. This study provides information about TAS2R38 diversity in a part of the world that is relatively understudied. Considering the two SNPs rs713598 and rs1726866, the CA nucleotide haplotype leading to the PV amino acid haplotype is extremely rare almost everywhere, but it is relatively frequent (between 6% and 15%) in northern Africa, where it coexists with the globally common amino acid haplotypes PA, AA, and AV. Given its higher frequency in North Africa, the authors propose the CA nucleotide haplotype as a biogeographic marker for forensic purposes.


Assuntos
Aminoácidos , Bioensaio , Humanos , África do Norte , Medicina Legal , Nucleotídeos
6.
Blood ; 129(19): 2616-2623, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28251914

RESUMO

High variability in patient outcome after rituximab-based treatment is partly explained by rituximab concentrations, and pharmacokinetic (PK) variability could be influenced by tumor burden. We aimed at quantifying the influence of baseline total metabolic tumor volume (TMTV0) on rituximab PK and of TMTV0 and rituximab exposure on outcome in patients with diffuse large B-cell lymphoma (DLBCL). TMTV0 was measured by 18F-fluorodeoxyglucose-positron emission tomography-computed tomography in 108 previously untreated DLBCL patients who received four 375 mg/m2 rituximab infusions every 2 weeks in combination with chemotherapy in 2 prospective trials. A 2-compartment population model allowed describing rituximab PK and calculating rituximab exposure (area under the concentration-time curve; AUC). The association of TMTV0 and AUC with metabolic response after 4 cycles, as well as progression-free survival (PFS) and overall survival (OS), was assessed using logistic regression and Cox models, respectively. Cutoff values for patient outcome were determined using receiver operating characteristic curve analysis. Exposure to rituximab decreased as TMTV0 increased (R2 = 0.41, P < .0001). A high AUC in cycle 1 (≥9400 mg × h per liter) was associated with better response (odds ratio, 5.56; P = .0006) and longer PFS (hazard ratio [HR], 0.38; P = .011) and OS (HR, 0.17; P = .001). A nomogram for rituximab dose needed to obtain optimal AUC according to TMTV0 was constructed, and the 375 mg/m2 classical dose would be suitable for patients with TMTV0 <281 cm3 In summary, rituximab exposure is influenced by TMTV0 and correlates with response and outcome of DLBCL patients. Dose individualization according to TMTV0 should be evaluated in prospective studies. These studies were registered at www.clinicaltrials.gov as #NCT00498043 and #NCT00841945.


Assuntos
Antineoplásicos/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Rituximab/uso terapêutico , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Rituximab/administração & dosagem , Rituximab/metabolismo , Rituximab/farmacocinética , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Adulto Jovem
7.
Blood ; 130(16): 1800-1808, 2017 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-28774879

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma. Although 5-year survival rates in the first-line setting range from 60% to 70%, up to 50% of patients become refractory to or relapse after treatment. Published analyses of large-scale outcome data from patients with refractory DLBCL are limited. SCHOLAR-1, an international, multicohort retrospective non-Hodgkin lymphoma research study, retrospectively evaluated outcomes in patients with refractory DLBCL which, for this study, was defined as progressive disease or stable disease as best response at any point during chemotherapy (>4 cycles of first-line or 2 cycles of later-line therapy) or relapsed at ≤12 months from autologous stem cell transplantation. SCHOLAR-1 pooled data from 2 phase 3 clinical trials (Lymphoma Academic Research Organization-CORAL and Canadian Cancer Trials Group LY.12) and 2 observational cohorts (MD Anderson Cancer Center and University of Iowa/Mayo Clinic Lymphoma Specialized Program of Research Excellence). Response rates and overall survival were estimated from the time of initiation of salvage therapy for refractory disease. Among 861 patients, 636 were included on the basis of refractory disease inclusion criteria. For patients with refractory DLBCL, the objective response rate was 26% (complete response rate, 7%) to the next line of therapy, and the median overall survival was 6.3 months. Twenty percent of patients were alive at 2 years. Outcomes were consistently poor across patient subgroups and study cohorts. SCHOLAR-1 is the largest patient-level pooled retrospective analysis to characterize response rates and survival for a population of patients with refractory DLBCL.


Assuntos
Linfoma Difuso de Grandes Células B/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Cooperação Internacional , Linfoma Difuso de Grandes Células B/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Estudos Observacionais como Assunto/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Estudos Retrospectivos , Terapia de Salvação , Resultado do Tratamento , Adulto Jovem
8.
Ann Hum Biol ; 46(2): 150-159, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30857436

RESUMO

Background: In Algeria, as in all North Africa, Berbers constitute the old background of the population. Today, Berber speakers account for only ∼ 25% of Algerians. This decline is the product of a complex human settlement from pre-history to recent invaders. Aim: This study aims to determine the genetic diversity level within a sample of five Algerian Berber speaking populations in order to contribute to resolving issues about the North African population settlement. Subjects and methods: Two Algerian Berber groups (Kabyle and Chaouia), originated from five administrative regions from Algeria, were typed for 11 Alu Insertions. Analysis has been based on Fst genetic distance, AMOVA, NMDS and distance to the centroid model. Results: No genetic differentiation has been observed between all Algerian Berbers discarding any geographical or ethnic effect. Comparative analyses based on Fst genetic distance did not show significant affinities between North Africans and either South Europeans or Middle Easterners, except genetic proximity between Algerians and Iberians. The amount of genetic diversity among Algerians and North African populations detected by the distance to the centroid model was significant compared with other North Mediterranean populations. Conclusion: A strong genetic homogeneity has been found between Algerian Berbers. Global genetic diversity based on Alu markers is following the isolation by distance model, except for some European populations.


Assuntos
Elementos Alu , Frequência do Gene , Variação Genética , Argélia , Alelos , Humanos , Polimorfismo Genético
9.
Am J Hum Biol ; 30(3): e23100, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29359455

RESUMO

OBJECTIVES: Through previous mitochondrial DNA studies, the Middle Eastern maternal genetic contribution to Tunisian populations appears limited. In fact, most of the studied communities were cosmopolitan, or of Berber or Andalusian origin. To provide genetic evidence for the actual contribution of Middle Eastern mtDNA lineages to Tunisia, we focused on two Arab speaking populations from Kairouan and Wesletia known to belong to an Arab genealogical lineage. MATERIALS AND METHODS: A total of 114 samples were sequenced for the mtDNA HVS-I and HVS-II regions. Using these data, we evaluated the distribution of Middle Eastern haplogroups in the study populations, constructed interpolation maps, and established phylogenetic networks allowing estimation of the coalescence time for three specific Middle Eastern subclades (R0a, J1b, and T1). RESULTS: Both studied populations displayed North African genetic structure and Middle Eastern lineages with a frequency of 12% and 28.12% in Kairouan and Wesletia, respectively. TMRCA estimates for haplogroups T1a, R0a, and J1b in Tunisian Arabian samples were around 15 000 YBP, 9000 to 5000 YBP, and 960 to 600 YBP, respectively. CONCLUSIONS: The Middle Eastern maternal genetic contribution to Tunisian populations, as to other North African populations, occurred mostly in deep prehistory. They were brought in different migration waves during the Upper Paleolithic, probably with the expansion of Iberomaurusian culture, and during Epipaleolithic and Early Neolithic periods, which are concomitant with the Capsian civilization. Middle Eastern lineages also came to Tunisia during the recent Islamic expansion of the 7th CE and the subsequent massive Bedouin migration during the 11th CE.


Assuntos
DNA Mitocondrial/análise , Variação Genética , Haplótipos/genética , Árabes/genética , Filogenia , Análise de Sequência de DNA , Tunísia
11.
Ann Hum Biol ; 44(2): 180-190, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27328643

RESUMO

BACKGROUND: Recent genomic analyses suggest that the current North African gene pool was mainly influenced by population flow coming from the East that altered the genetic structure of autochthonous Berber populations. Such genetic flow has not been extensively addressed yet using North African populations of Middle-eastern origin as reference. AIM: To discern the Middle-eastern component in the genetic background of Tunisian Arabs and evaluate the extent of gene flow from the Middle East into North African autochthonous Berber populations. SUBJECTS AND METHODS: This study has examined 113 Tunisians of well-known Arabian origin from Kairouan region, using 15 autosomal Short Tandem Repeats (STRs) loci. RESULTS: No deviations from Hardy-Weinberg equilibrium were observed and all loci presented high levels of heterozygosity. Principal coordinate and STRUCTURE analyses were consistent in clustering together North African and Middle Eastern populations, likely reflecting the recent gene flow from the East dating back to the Arab conquest period. This demographic migration and the Arabisation process that submerged the original Berber language and customs seems to have be accompanied by substantial gene flow and genetic admixture. CONCLUSION: This study represents an additional step to obtain a comprehensive understanding of the complex demographic history of North African populations.


Assuntos
Fluxo Gênico , Variação Genética , Repetições de Microssatélites , Árabes/genética , Humanos , Tunísia
12.
Am J Phys Anthropol ; 161(1): 62-71, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27192181

RESUMO

OBJECTIVES: North Africa has a complex demographic history of migrations from within Africa, Europe, and the Middle East. However, population genetic studies, especially for autosomal genetic markers, are few relative to other world regions. We examined autosomal markers for eight Tunisian and Libyan populations in order to place them in a global context. MATERIALS AND METHODS: Data were collected by TaqMan on 399 autosomal single nucleotide polymorphisms on 331 individuals from Tunisia and Libya. These data were combined with data on the same SNPs previously typed on 2585 individuals from 57 populations from around the world. Where meaningful, close by SNPs were combined into multiallelic haplotypes. Data were evaluated by clustering, principal components, and population tree analyses. For a subset of 102 SNPs, data from the literature on seven additional North African populations were included in analyses. RESULTS: Average heterozygosity of the North African populations is high relative to our global samples, consistent with a complex demographic history. The Tunisian and Libyan samples form a discrete cluster in the global and regional views and can be separated from sub-Sahara, Middle East, and Europe. Within Tunisia the Nebeur and Smar are outlier groups. Across North Africa, pervasive East-West geographical patterns were not found. DISCUSSION: Known historical migrations and invasions did not displace or homogenize the genetic variation in the region but rather enriched it. Even a small region like Tunisia contains considerable genetic diversity. Future studies across North Africa have the potential to increase our understanding of the historical demographic factors influencing the region. Am J Phys Anthropol 161:62-71, 2016. © 2016 The Authors American Journal of Physical Anthropology Published by Wiley Periodicals, Inc.


Assuntos
Variação Genética/genética , Migração Humana , Antropologia Física , Europa (Continente) , Genética Populacional , Haplótipos/genética , Humanos , Líbia , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal , Tunísia
14.
Mol Genet Genomic Med ; 10(3): e1871, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35128830

RESUMO

BACKGROUND: The single nucleotide polymorphisms (SNPs) of the dopamine D3 receptor (DRD3), the CUB and sushi multiple domains 1 (CSMD1) and the neuregulin 1 (NRG1) genes were used to study the genetic diversity and affinity among North African populations and to examine their genetic relationships in worldwide populations. METHODS: The rs3773678, rs3732783 and rs6280 SNPs of the DRD3 gene located on chromosome 3, the rs10108270 SNP of the CSMD1 gene and the rs383632, rs385396 and rs1462906 SNPs of the NRG1 gene located on chromosome 8 were analysed in 366 individuals from seven North African populations (Libya, Kairouan, Mehdia, Sousse, Kesra, Smar and Kerkennah). RESULTS: The low values of FST indicated that only 0.27%-1.65% of the genetic variability was due to the differences between the populations. The Kairouan population has the lowest average heterozygosity among the North African populations. Haplotypes composed of the ancestral alleles ACC and ACAT were more frequent in the Kairouan population than in other North African populations. The PCA and the haplotypic analysis showed that the genetic structure of populations in North Africa was closer to that of Europeans, Admixed Americans, South Asians and East Asians. However, analysis of the rs3732783 and rs6280 SNPs revealed that the CT microhaplotype was specific to the North African population. CONCLUSIONS: The Kairouan population exhibited a relatively low rate of genetic variability. The North African population has undergone significant gene flow but also evolutionary forces that have made it genetically distinct from other populations.


Assuntos
Polimorfismo de Nucleotídeo Único , Receptores de Dopamina D3 , População Negra , Genótipo , Haplótipos , Humanos , Proteínas de Membrana/genética , Neuregulina-1/genética , Receptores de Dopamina D3/genética , Proteínas Supressoras de Tumor/genética , Estados Unidos
15.
Gene ; 777: 145466, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33524518

RESUMO

The dopamine - related genes, like dopamine D2 receptor (DRD2) gene and ankyrin repeat and kinase domain containing 1 (ANKK1) gene are implicated in neurological functions. Some polymorphisms of the DRD2/ANKK1 locus (TaqIA, TaqIB, TaqID) have been used to study genetic diversity and the evolution of human populations. The present investigation aims to assess the genetic diversity in seven North African populations in order to explore their genetic structure and to compare them to others worldwide populations studied for the same locus. Nine single nucleotide polymorphisms (SNPs) from the DRD2/ANKK1 locus (rs1800497 TaqIA, rs2242592, rs1124492, rs6277, rs6275, rs1079727, rs2002453, rs2234690 and rs1079597 TaqIB) were typed in 366 individuals from seven North African populations: six from Tunisia (Sousse, Smar, Kesra, Kairouan, Mehdia and Kerkennah) and one from Libya. The allelic frequencies of rs2002453 and rs2234690 were higher in the Smar population than in the other North African populations. More, the Smar population showed the lowest average heterozygosity (0.313). The principal component analysis (PCA) showed that the Smar population was clearly separated from others. Furthermore, linkage disequilibrium analysis shown a high linkage disequilibrium in the North African population and essentially in Smar population. Comparison with other world populations has shown that the heterozygosity of North African population was very close to that of the African and European populations. The PCA and the haplotypic analysis suggested the presence of an important Eurasian genetic component for the North African population. These results suggested that the Smar population was isolated from the others North Africans ones by its peculiar genetic structure because of isolation, endogamy and genetic drift. On the other hand, the North African population is characterized by a multi ancestral gene pool from Eurasia and sub-Saharan Africa due to human migration since prehistoric times.


Assuntos
Proteínas Serina-Treonina Quinases/genética , Receptores de Dopamina D2/genética , Adulto , África do Norte/etnologia , Alelos , População Negra , Etnicidade/genética , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Genômica , Genótipo , Técnicas de Genotipagem , Haplótipos/genética , Heterozigoto , Migração Humana , Humanos , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
16.
Mol Genet Genomic Med ; 9(8): e1744, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34251094

RESUMO

BACKGROUND: Only a few studies have investigated the association of single nucleotide polymorphisms in STAT3 gene with the susceptibility to cancer and response to chemotherapy. Our aim was to determine the allele frequencies of rs3869550, rs957971, and rs7211777 at the STAT3 gene in North African populations and compare them to 1000 genomes populations, and to investigate their relation with cancer. METHODS: The targeted SNPs have been analyzed in six Tunisian populations and a sample of Libyans using TaqMan® Assay. The results were compared to 1000 Genomes Project population samples. Targeting of the regions encompassing the three SNPs by micro-ARN was assessed using miR databases. RESULTS: The analysis of the 3 SNPs showed that North African populations were close to South Asians. As expected, African populations presented a significant frequency of the ancestral CCG haplotype in contrast to other populations where the fully derived TGA haplotype was more frequent. The presence and diversity of rare haplotypes at STAT3 in North African populations could have been generated by recombination between the two major haplotypes. A screening of the micro-RNA databases showed that the STAT3 region with the mutated allele of rs7211777 (G>A) could be targeted by miR hsa-miR-3606-5p, which also targets genes involved in breast cancer.


Assuntos
Neoplasias da Mama/genética , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT3/genética , Feminino , Haplótipos , Humanos , Tunísia
17.
Sci Rep ; 11(1): 15728, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344940

RESUMO

To obtain refreshed insights into the paternal lineages of Tunisian populations, Y-chromosome diversity was assessed in two populations belonging to an Arab genealogical lineage, Kairouan and Wesletia, as well as in four Tunisian Andalusian populations, Testour, Slouguia, Qalaat-El-Andalous and El Alia. The Arabs from Kairouan revealed 73.47% of E-M81 and close affinities with Berber groups, indicating they are likely arabized Berbers, clearly differentiated from the Arabs from Wesletia, who harbored the highest frequency (71.8%) of the Middle Eastern component ever observed in North Africa. In the Tunisian Andalusians, the North African component largely prevailed, followed by the Middle Eastern contribution. Global comparative analysis highlighted the heterogeneity of Tunisian populations, among which, as a whole, dominated a set of lineages ascribed to be of autochthonous Berber origin (71.67%), beside a component of essentially Middle Eastern extraction (18.35%), and signatures of Sub-Saharan (5.2%), European (3.45%) and Asiatic (1.33%) contributions. The remarkable frequency of T-M70 in Wesletia (17.4%) prompted to refine its phylogeographic analysis, allowing to confirm its Middle Eastern origin, though signs of local evolution in Northern Africa were also detected. Evidence was clear on the ancient introduction of T lineages into the region, probably since Neolithic times associated to spread of agriculture.


Assuntos
Árabes/genética , Cromossomos Humanos Y/genética , Genética Populacional , Haplótipos , Herança Paterna , Humanos , Masculino , Tunísia
18.
Gene ; 696: 186-196, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30790653

RESUMO

The COMT gene encodes for catechol-O-methyl-transferase, an enzyme playing a major role in regulation of synaptic catecholamine neurotransmitters. Investigating 4 markers of the COMT gene (rs2020917, rs4818, rs4680, rs9332377) in 6 Tunisian populations and a pool of Libyans. Our objective was to determine the distribution of allelic, genotypic and haplotypic frequencies by comparison to other populations of the 1000 genomes project and 59 populations from the Kidd Lab dataset. The allelic frequencies established for these SNPs in the North African populations are similar to those of Europeans and South Asians. Linkage disequilibrium between these SNPs and haplotypes frequencies are different between populations whose clustering in principal components analysis (PCA) according to their geographic origin was more significant using haplotypic frequencies. COMT activity prediction by haplotypes genotyping could be limited to rs4818-rs4680 micro-haplotypes. The Low activity haplotype (CG) displays the highest frequency in African populations (55%), in the 59 Kidd Lab populations we found also that Sub-Saharan Africans, Native Americans, and some East Asian and Pacific Island populations all have frequencies in the 50-81% range for (CG) where as its lowest frequency was found in Europeans (10%), this results have been also confirmed for Southwest Asians. North Africans and South Asians with intermediate frequencies have approximately similar values (20% and 25%). Europeans show the highest frequencies of haplotypes with predicted High and Medium activity in contrast to Africans. North Africans and South Asians present similar results for all the category of the COMT activity prediction by haplotypes genotyping. The high level of genetic diversity of COMT haplotypes, not only allows distinction between populations according to their history settlement, origin and ethnicity, it constitutes a basis for studies of association of the COMT gene polymorphism with pathologies, drugs response and for forensic investigation in North African populations.


Assuntos
População Negra/genética , Catecol O-Metiltransferase/genética , Frequência do Gene/genética , Desequilíbrio de Ligação/genética , Polimorfismo de Nucleotídeo Único/genética , Aclimatação/genética , África do Norte , Alelos , Catecol O-Metiltransferase/metabolismo , Genética Forense/métodos , Haplótipos/genética , Voluntários Saudáveis , Humanos , Farmacogenética/métodos
19.
Eur J Hum Genet ; 27(12): 1885-1893, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31285530

RESUMO

The set of 55 ancestry informative SNPs (AISNPs) originally developed by the Kidd Lab has been studied on a large number of populations and continues to be applied to new population samples. The existing reference database of population samples allows the relationships of new population samples to be inferred on a global level. Analyses show that these autosomal markers constitute one of the better panels of AISNPs. Continuing to build this reference database enhances its value. Because more than half of the 25 ethnic groups recently studied with these AISNPs are from Southwest Asia and the Mediterranean region, we present here various analyses focused on populations from these regions along with selected reference populations from nearby regions where genotype data are available. Many of these ethnic groups have not been previously studied for forensic markers. Data on populations from other world regions have also been added to the database but are not included in these focused analyses. The new population samples added to ALFRED and FROG-kb increase the total to 164 population samples that have been studied for all 55 AISNPs.


Assuntos
Etnicidade/genética , Genética Populacional , Polimorfismo de Nucleotídeo Único/genética , Grupos Raciais/genética , Povo Asiático/genética , Europa (Continente)/epidemiologia , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Região do Mediterrâneo/epidemiologia
20.
Eur J Dermatol ; 18(4): 412-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18573714

RESUMO

In this study, perceived stress and quality of life were measured with PCV-Metra and SF-12 scales in outpatients consulting for different dermatoses in 5 academic dermatology departments for 5 consecutive days. 658 patients were enrolled in the study. Perceived stress was higher in women and the mental component of their quality of life was more altered. Perceived stress was higher in Paris than in other areas and was respectively 11.4, 10.4, 9.2 and 8.9 for psoriasis, acne, atopic dermatitis and pigmented tumours. Perceived stress was correlated to mental quality of life. Stress was more elevated in people with inflammatory dermatoses than in those with tumours. To our knowledge, this is the first comparative study of both stress and quality of life levels in different dermatoses. Stress levels were lower in people with pigmented tumours, suggesting that they can be used as controls in comparative studies because they can be considered as healthy subjects. On the contrary, patients with psoriasis had a very high level of perceived stress and a deeply altered quality of life.


Assuntos
Qualidade de Vida , Dermatopatias/psicologia , Estresse Psicológico/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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