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The first large-scale fine characterization of Tunisian H lineages clarifies that the post-Last glacial maximum expansion originating in Iberia hot only led to the resettlement of Europe but also of North Africa. We found that 46% of 81 Tunisian H lineages subscreened for 1,580 bp in mtDNA coding region were affiliated with H1 and H3 subhaplogroups, which are known to have originated in Iberia. Although no signs of local expansion were detected, which would allow a clear dating of their introduction, the younger and less diverse Tunisian H1 and H3 lineages indicate Iberia as the radiating centre. Major contributions from historical migrations to this Iberian genetic imprint in Tunisia were ruled out by the mtDNA gene pool similarity between Berber/Arab/cosmopolitan samples and some 'Andalusian' communities, settled by the descendents of the 'Moors' who once lived in Iberia for 10 centuries (between 8th and 17th centuries), before being expelled to Tunisia. KEY WORDS mtDNA; haplogroup H; Tunisia; Andalusians

Tuberculosis is a contagious bacterial infection disease caused by the Koch bacillus (Mycobacterium tuberculosis: M.tb) that usually attacks the lungs, but sometimes also other parts of the body. This disease has been on the rise for some 15 years. Bacille Calmette-Guérin (BCG) is currently the only vaccine used to protect against tuberculosis. It is very useful in preventing severe disease in young children, but it does not protect reliably adult and immunodeficiency patients. So, the development of a safe vaccine that is more effective than BCG in eradicating tuberculosis in adults is a major goal of the public health. In view that infection caused by M.tb has proved recently to stimulate strongly the humoral immunity against adhesin such as (hsp70). Therefore, the aim of our study is the using of the immunoinformatic tools to predict the best linear B cell epitopes from "DnaK" adhesin (hsp70). Three best potential linear B cell epitopes ("DKGEKEQRILVFDL", "AKIELSSSQSTSINLPYIT" and "HPGGEPGGAHPG") were found to fulfill all the criteria for becoming an ideal B cell epitope. In addition the safety of these epitopes was evaluated using in silico techniques. In order to verify the binding cleft interaction between the selected epitopes and the antibody we used a docking method. Our computational study allows us to predict and design three novel epitope-based vaccines or which in another target could be used in diagnosis of M.tb infection. [ABSTRACT FROM AUTHOR]

Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. The aim of this study was to investigate the role of IL10-1082 and IFN-y+874 polymorphisms in susceptibility to cervical cancer among Tunisian women. Study Design. The IL10-1082 and IFN-7#947;+874 polymorphisms were analyzed by ARMS-PCR in 160 healthy women and 122 with cervical cancer. The search for associations between those polymorphisms and cervical cancer was based on the χ² test or Fisher's exact test. Results. The IFN-γ+874 polymorphism showed significant increased frequency of T allele in healthy controls compared with patients (OR = 0.71, 95% CI = 0.50-1.01, and P = 0.0459) and individuals with homozygote IFN-γ+874 T/T genotype were at lesser risk of cervical cancer (OR = 0.53, 95% CI = 0.31-0.92, and P = 0.015). However, carriers of allele have higher risk for developing cervical cancer (OR = 1.88, 95% CI = 1.09-3.24, and P = 0.015). At the polymorphic nucleotide in position 1082 of the IL10 promoter, no differences were found between patients and controls subjects. Conclusion. Our study shows that the T/T genotype polymorphism of IFN-γ+874 T>A is a protective factor for cervical cancer among Tunisian women. [ABSTRACT FROM AUTHOR]

The present study was undertaken to investigate the association between Hepatitis B Virus (HBV) infection and polymorphisms of tumour necrosis factor alpha TNF-α − 308 G > A, TNF-α − 238 G > A and TNF RII VNTR (p75) gene promoter in a Tunisian population. Blood samples were collected from 100 Tunisian patients with HBV infection, 45 with Chronic Hepatitis (CH), 36 with Liver Cirrhosis (LC), 15 with Hepatocellular Carcinoma (HCC) and 200 healthy individuals of similar ethnicity. Genomic DNA was extracted from peripheral blood leukocytes. Genotyping of the analysed polymorphisms was performed using Amplified Refractory Mutation System-Polymerase Chain Reaction (ARMS-PCR), Restriction Fragment Length Polymorphism (RFLP) and Variable Number Tandem Repeat PCR (PCR-VNTR). The variant homozygotes − 308 GG were associated with 50% decreased risk of HBV chronic infection (GG vs AA + GA; p = 0.010; OR = 0.50; 95%CI = 0.29–0.85). However, the carriers of minor allele − 308 A have higher risk (1.5 times) to develop a chronic infection than other patients ( p = 0.027; OR = 1.46; 95%CI = 1.04–2.06). The minor allele of − 238 polymorphism was positively associated with virus resistance and the development of chronic infection ( p = 0.043; OR = 1.42; 95%CI = 1.01 1.99). The distribution of − 308, − 238 and TNF RII VNTR (p75) among the three groups differed significantly. For HCC groups, there were statistically significant differences in allele distribution in − 308, − 238 respectively in which A allele remains a risk factor for HBV evolution to HCC ( p = 0.008 and p = 0.026). Haplotype analysis revealed that TNF-α (− 308A; − 238A) was significantly associated to HBV chronic infection and moreover to disease aggravation to HCC stage. Our findings imply that variations in the genes governing the levels of constitutive and inducible TNF-α and TNF RII might be an important risk factor, which could explain the variable outcomes of HBV infection. [ABSTRACT FROM AUTHOR]

Introduction: Previous studies have highlighted the importance of polymorphisms of toll-like receptors (TLRs) in the pathogenesis of certain cancers, including head and neck cancers (HNC)., Aim of the Study: The aim of this study was to evaluate the association of TLR2 (-196 to -174 ins/del) and TLR3 (1377 C>T) as potential risk factors for HNC in Tunisians., Material and Methods: A case-control study including 246 HNC patients (174 nasopharyngeal carcinoma - NPC and 72 laryngeal cancer - LC) and 250 healthy controls. Genotyping was done by using PCR and PCR-RFLP methods., Results: Higher minor allele frequencies of TLR2 (-196 to -174 ins/del) and TLR3 1377 C>T polymorphisms were seen in HNC, NPC, and LC compared to controls. In addition, higher increased HNC, NPC, and LC risk was associated with TLR2 ins/del and TLR2 del/del genotypes (p < 0.0001). Positive association with HNC, NPC, and LC risk was seen with TLR2 del-containing genotypes (ins/del + del/del) (p < 0.0001). The T/T genotype of TLR3 is associated with HNC, NPC, and LC susceptibility (p < 0.0001). Positive association with HNC and NPC risk was seen with TLR3 T allele carriers (C/T + T/T) (p < 0.0001). Increased frequency of T-ins, C-del, and T-del haplotypes was revealed in HNC and NPC cases than healthy controls; however, T-del was significantly higher in LC cases., Conclusions: Our results demonstrate an increased risk of HNC, NPC, and LC with TLR2 ins/del, TLR2 del/del, and TLR3 T/T genotypes. And positive association with T-ins, C-del, and T-del haplotypes with HNC and NPC and T-del haplotype with LC., Competing Interests: The authors declare no conflict of interest.

Aim: The aim of this work was to study the correlation between the mitochondrial microsatellite, situated between the nucleotides 303 and 315 of the mitochondrial genome and the breast cancer in Tunisia., Materials and Methods: We have analyzed, by PCR-sequencing, the polymorphism of a mitochondrial microsatellite in 40 Tunisian patients and 39 healthy Tunisian donors. Comparisons of epidemiologic and sequences data were performed by chi-2 test., Results: We have revealed, for this mitochondrial microsatellite, seven different haplotypes in patients and five different haplotypes in controls. The haplotypic distribution was not significant between patients and controls but a negative association between one of these haplotypes (309+C 315+C) and the lymph node invasion was found., Conclusion: The haplotype 309+C 315+C is negatively correlated with lymph node invasion of breast cancer in Tunisia.

HLA system plays a key role in the tumor cells' escape from immune surveillance. Herein is the first report on the correlation of the susceptibility to breast cancer with HLA class II markers in Tunisia. Molecular typing of HLA-DRB1 and -DQB1 loci was undertaken for 70 Tunisian female patients. Comparison of allele and haplotype distribution between patients and 70 female control subjects reveals a negative association between HLADRB1* 07-DQB1*02 and the incidence of breast cancer in the Tunisian population.