Apolipoprotein gene polymorphisms and plasma levels in healthy Tunisians and patients with coronary artery disease

<p>Abstract</p> <p>Aim</p> <p>To analyze apolipoprotein gene polymorphisms in the Tunisian population and to check the relation of these polymorphisms and homocysteine, lipid and apolipoprotein levels to the coronary artery disease (CAD).</p> <p>Methods</p> <p>In healthy blood donors and in patients with CAD complicated by myocardial infarction (MI) four apolipoprotein gene polymorphisms [APO (a) PNR, APO E, APO CI and APO CII] were determined and plasma levels of total homocysteine, total cholesterol (TC), triglycerides (TG), HDL-cholesterol (HLD-C) and apolipoproteins (apo A-I, Apo B, Apo E) were measured.</p> <p>Results</p> <p>Analysis of the four apolipoprotein gene polymorphisms shows a relative genetic homogeneity between Tunisian population and those on the other side of Mediterranean basin. Compared to controls, CAD patients have significantly higher main concentrations of TC, TG, LDL-C, apo B and homocysteine, and significantly lower ones of HDL-C, apo A-I and apo E. The four apolipoprotein gene polymorphisms have not showed any significant differences between patients and controls. However, the APO E4 allele appears to be associated to the severity of CAD and to high levels of atherogenic parameters and low level of apo E, which has very likely an anti-atherogenic role.</p> <p>Conclusion</p> <p>Although APO (a) PNR, APO CI and APO CII genes are analyzed in only few populations, they show a frequency distribution, which is not at variance with that of APO E gene and other widely studied genetic markers. In the Tunisian population the APO E 4 appears to be only indirectly involved in the severity of CAD. In the routine practice, in addition of classic parameters, it will be useful to measure the concentration of apo E and that of Homocysteine and if possible to determine the APO E gene polymorphism.</p

Research of the origin of a particular Tunisian group using a physical marker and Alu insertion polymorphisms

The aim of this study was to show how, in some particular circumstances, a physical marker can be used along with molecular markers in the research of an ancient people movement. A set of five Alu insertions was analysed in 42 subjects from a particular Tunisian group (El Hamma) that has, unlike most of the Tunisian population, a very dark skin, similar to that of sub-Saharans, and in 114 Tunisian subjects (Gabes sample) from the same governorate, but outside the group. Our results showed that the El Hamma group is genetically midway between sub-Saharan populations and North Africans, whereas the Gabes sample is clustered among North Africans. In addition, The A25 Alu insertion, considered characteristic to sub-Saharan Africans, was present in the El Hamma group at a relatively high frequency. This frequency was similar to that found in sub-Saharans from Nigeria, but significantly different from those found in the Gabes sample and in other North African populations. Our molecular results, consistent with the skin color status, suggest a sub-Saharan origin of this particular Tunisian group

Analysis of Genomic Regions Associated With Coronary Artery Disease Reveals Continent-Specific Single Nucleotide Polymorphisms in North African Populations.

ACKGROUND: In recent years, several genomic regions have been robustly associated with coronary artery disease (CAD) in different genome-wide association studies (GWASs) conducted mainly in people of European descent. These kinds of data are lacking in African populations, even though heart diseases are a major cause of premature death and disability. METHODS: Here, 384 single nucleotide polymorphisms (SNPs) in the top four CAD risk regions (1p13, 1q41, 9p21, and 10q11) were genotyped in 274 case-control samples from Morocco and Tunisia, with the aim of analyzing for the first time if the associations found in European populations were transferable to North Africans. RESULTS: The results indicate that, as in Europe, these four genetic regions are also important for CAD risk in North Africa. However, the individual SNPs associated with CAD in Africa are different from those identified in Europe in most cases (1p13, 1q41, and 9p21). Moreover, the seven risk variants identified in North Africans are efficient in discriminating between cases and controls in North African populations, but not in European populations. CONCLUSIONS: This study indicates a disparity in markers associated to CAD susceptibility between North Africans and Europeans that may be related to population differences in the chromosomal architecture of these risk regions

The X chromosome Alu insertions as a tool for human population genetics: data from European and African human groups.

International audienceAlu elements are the most abundant mobile elements in the human genome (approximately 1,100,000 copies). Polymorphic Alu elements have been proved to be useful in studies of human origins and relationships owing to two important advantages: identity by descent and absence of the Alu element known to be the ancestral state. Alu variation in the X chromosome has been described previously in human populations but, as far as we know, these elements have not been used in population relationship studies. Here, we describe the allele frequencies of 13 'young' Alu elements of the X chromosome (Ya5DP62, Ya5DP57, Yb8DP49, Ya5a2DP1, Yb8DP2, Ya5DP3, Ya5NBC37, Yd3JX437, Ya5DP77, Ya5NBC491, Yb8NBC578, Ya5DP4 and Ya5DP13) in six human populations from sub-Saharan Africa (the Ivory Coast), North Africa (Moroccan High Atlas, Siwa oasis in Egypt, Tunisia), Greece (Crete Island) and Spain (Basque Country). Eight out of 13 Alu elements have shown remarkably high gene diversity values in all groups (average heterozygosities: 0.342 in the Ivory Coast, 0.250 in North Africa, 0.209 in Europe). Genetic relationships agree with a geographical pattern of differentiation among populations, with some peculiar features observed in North Africans. Crete Island and the Basque Country show the lowest genetic distance (0.0163) meanwhile Tunisia, in spite of its geographical location, lies far from the other two North African samples. The results of our work demonstrate that X chromosome Alu elements comprise a reliable set of genetic markers useful to describe human population relationships for fine-scale geographical studies

UDP-glucuronosyltransferase genetic variation in North African populations: a comparison with African and European data

Background: Genetic variation in glucuronosyltransferases (UGT) is crucial in drug metabolism and risk of some diseases. Aim: To examine genetic variation in UGT in North African populations. Subjects and methods: Allele frequencies of SNPs UGT1A424Thr, UGT1A448Val, UGT2B1585Tyr, UGT2B15523Thr and UGT2B17 CNV deletion from Morocco, Algeria, Tunisia and Libya were compared to European and Sub-Saharan populations. Results: North Africans are the group with the highest genetic heterogeneity given by internal differences in the occurrence of UGT2B17 deletion, UGT1A448Val and UGT1A4 haplotypes. UGT2B15 SNPs differentiate Sub-Saharans from the rest of the populations. Conclusion: North African populations show a high frequency of carriers of UGT2B15523Thr, a variant linked to an increased risk of prostate cancer. High Atlas Moroccans and Algerians show low frequency of UGT2B17del, a variant associated with high concentrations of testosterone and oestradiol.This work was financed by the grant ‘Ajut per potenciar sin���ergies en recerca’ awarded by the Faculty of Biology, University of Barcelona (2016 and 2017), the project 2016/UEM 39 of the Universidad Europea de Madrid, and by the 2017 SGR 1630 Grup de Recerca en Antropologia Biol���ogica (GREAB).1.588 JCR (2018) Q2, 26/90 Anthropology; Q3, 84/164 Public, Environmental & Occupational Health, 51/87 Biology0.616 SJR (2018) Q2, 208/562 Public Health, Environmental and Occupational Health; Q3, 67/106 Epidemiology, 112/188 Physiology, 226/351 Genetics, 23/36 AgingNo data IDR 2018UE

Cytochrome and sulfotransferase gene variation in North African populations

The aim of this study is to describe the diversity of four cytochrome and four sulfotransferase polymorphisms in six north African samples. Scarce data have been compiled for these samples despite the rich genetic background of north African populations. CYP3A4*1B, CYP3A4*17, CYP3A4*3, CYP3A5*3, SULT1A1*2, SULT1A2*2, SULT1A2*3 and SULT1E1*2 polymorphisms were explored in 556 individuals from Morocco, Algeria, Tunisia and Libya. Allele frequencies in our samples largely exceeded the variation ranges described for European populations, especially for CYP3A4*1B, SULT1A1*2 and SULT1A2*3. North African populations are heterogeneous, genetically diverse and show a considerable sub-Saharan African contribution for markers associated with increased risk of prostate cancer and with differential drug metabolism.UEM (2015/31)2.350 JCR (2016) Q3, 132/257 Pharmacology and PharmacyUE