Allelic frequencies of 22 short tandem repeats loci and tri-allelic patterns of Penta D and TPOX identified in Gabonese population.

Short tandem repeats (STRs) are repeating DNA sequences used in forensic human identity testing and the diagnosis of aneuploidies. Many STRs like Penta D and TPOX are used routinely for paternity tests, but these tests are not widely used in sub-Saharan Africa. In this study we recruited individuals from Gabonese families seeking a paternity test. After DNA extraction from buccal swabs, we genotyped samples using a panel of 22 STRs. A total of 115 unrelated subjects from 39 families were included. Allele frequencies of the 22 STR loci were determined in unrelated Gabonese subjects. The most polymorphic loci were D21S11 (16 alleles) and FGA (17 alleles), while D3S1358 and TH01 loci were less polymorphic, with five alleles each. Deviation from Hardy-Weinberg equilibrium was observed for TPOX, D3S1358, CSFPO and D7S820 loci. We reported tri-allelic patterns that indicate aneuploidies at a combined frequency of 4% (4/115) with 3% for Penta D (1/35) and 3% for TPOX (3/102). Furthermore, we identified a new tri-allelic genotype 5-8-16 for the Penta D locus located on chromosome 21 in a healthy subject. In addition, we observed three tri-allelic variants of TPOX, located on chromosome 2, in healthy subjects, namely 8-10-11, 8-9-10, and 8-8-10. Our study revealed unsuspected polymorphic variations in Penta D and TPOX for the first time in Gabon, raising several questions about chromosomal disorders. Further population genetics studies are needed in Gabon to better characterize these variations, both qualitatively and quantitative.

Plasmatic neuroglobin during the primitive open-angle glaucoma.

OBJECTIVE: Elucidate the relation between neuroglobin and the primitive open-angle glaucoma. PATIENTS AND METHODS: This cross-sectional case-control study involved 64 patients with primitive open-angle glaucoma on 2 eyes and 64 control subjects. Glaucoma was classified as early, moderate or severe according to ophthalmological examination. Then we determined neuroglobin concentration and compared his ROC curve with characteristics of glaucoma. Chi-square test was used to compare proportions and spearman test for correlations between quantitative variables. RESULTS: Neuroglobin concentrations were higher among patients with glaucoma compared to control's (4.7±4.6 ng/mL versus 0.9±1.1 ng/mL, p=0.0000). Neuroglobin concentration was related to visual acuity, to the cup/disc ratio (eye right: r=0.340, p=0.006 and left eye: r=0.413, p=0.001). In addition, neuroglobin concentration was correlated with duration (r=0.565; p=0.000) and glaucoma severity (r=0.506, p=0.000). The area under the curve of neuroglobin concentration was 0.82 compared to that of intra ocular pressure (0.70). CONCLUSION: This study suggests that neuroglobin could be used as biomarker for glaucoma diagnosis.

[Lipid, lipoproteins and atherogenesis profiles in sickle cell disease among Central African patients]. / Évaluation du profil lipoprotéique et du risque athérogène chez les drépanocytaires homozygotes et hétérozygotes de Brazzaville.

Lipid and lipopproteins disorders are well established in sera from sickle cell disease (SCD) patients out of Central Africa. The present case-control study was conducted to compare serum levels of total cholesterol (TC), HDL-C, triglycerides (TG), LDL-C and TC/HDL-C ratio (atherogenic index) from SCD homozygotes (SS) in steady state, SCD heterozygotes (AS) and controls (AA) in Brazzaville, Congo. Significant reductions of TC and LDL-C vs. increase in TG were reported in SS. However, significant decrease in HDL-C and increase in atherogenic index were observed in AS. We recommend prevention of oxidative stress, dyslipidemia and atherosclerosis in SCD using hygiene-diet measures. Only longitudinal studies in large populations will provide pathophysiological basis of lipid and lipoproteins disorders in SCD.

[Profile of immunoglobulins A, G, and M during breast milk maturation in a tropical area (Gabon)]. / Profil des immunoglobulines A, G et M au cours de la maturation du lait maternel en milieu tropical (Gabon).

OBJECTIVES: To study the maturation of breast milk by the course of immunoglobulins A, G and M during the first three weeks of breast feeding. MATERIAL AND METHODS: This longitudinal and prospective survey took place from August to October, 2007, in Libreville, the capital of Gabon. The population comprised women with no significant medical history who had given birth in the obstetrics department of Center Hospital of Libreville. Women who delivered at home, had stillbirths, or infants positive for HIV hepatitis B virus were excluded. Three samples were taken, on D1 for colostrum, D7 for the transitional milk and D21 for mature milk. Immunoglobulins were determined by nephelometry, with the Turbox Plus(®) system from Diagnostica Orion. Variables were compared with Spearman's non-parametric test. The survey of the kinetic has been made from the test of Friedman's test was used to assess the kinetics. Significance was set at p<0.05. RESULTS: This survey included 60 mother-child pairs. The mean IgA concentration on D1 was 13.4 ± 5.9 g/L. This concentration fell very quickly by the end of the first week, to 2.3 ±â€Š2.0 g/L on D8, and then stabilized through D21. This rapid drop explains the need for early breast feeding after birth. On the other hand, IgG and IgM concentrations varied less and about one-sixth as high as the IgA. This finding confirms that they were minor components of breast milk. CONCLUSION: This work shows the importance of the early immune protection provided by the mother to her child during the first week of life.