The limitations of kinship determinations using STR data in ill-defined populations.

The likelihood ratio (LR) method is commonly used to determine kinship in civil, criminal, or forensic cases. For the past 15 years, our research group has also applied LR to ancient STR data and obtained kinship results for collections of graves or necropolises. Although we were able to reconstruct large genealogies, some pairs of individuals showed ambiguous results. Second-degree relationships, half-sibling pairs for example, were often inconsistent with detected first-degree relationships, such as parent/child or brother/sister pairs. We therefore set about providing empirical estimations of the error rates for the LR method in living populations with STR allelic diversities comparable to that of the ancient populations we had previously studied. We collected biological samples in the field in North-Eastern Siberia and West Africa and studied more than 800 pairs of STR profiles from individuals with known relationships. Because commercial STR panels were constructed for specific regions (namely Europe and North America), their allelic makeup showed a significant deficit in diversity when compared to European populations, replicating a situation often faced in ancient DNA studies. We assessed the capacity of the LR method to confirm known relationships (effectiveness) and its capacity to detect those relationships (reliability). Concerns over the effectiveness of LR determinations are mostly an issue in forensic studies, while the reliability of the detection of kinship is an issue for the study of necropolises or other large gatherings of unidentified individuals, such as disaster victims or mass graves. We show that the application of LR to both test populations highlights specific issues (both false positives and false negatives) that prevent the confirmation of second-degree kinship or even full siblingship in small populations. Up to 29% of detected full sibling relationships were either overestimated half-sibling relationships or underestimated parent-offspring relationships. The error rate for detected half-sibling relationships was even higher, reaching 41%. Only parent-offspring pairs were reliably detected or confirmed. This implies that, in populations that are small, ill-defined, or for which the STR loci analyzed are inappropriate, an examiner might not be able to distinguish a pair of full siblings from a pair of half-siblings. Furthermore, half-sibling pairs might be overlooked altogether, an issue that is exacerbated by the common confusion, in many languages and cultures, between half-siblings and full siblings. Consequently, in the study of ancient populations, human remains of unknown origins, or poorly surveyed modern populations, we recommend a conservative approach to kinship determined by LR. Next-generation sequencing data should be used when possible, but the costs and technology involved might be prohibitive. Therefore, in potentially contentious situations or cases lacking sufficient external information, uniparental markers should be analyzed: ideally, complete mitochondrial genomes and Y-chromosome haplotypes (STR, SNP, and/or sequencing).

[Evaluation of the immunization status against hepatitis B and of the prevalence of Ag HBs among Beninese soldiers participating in military missions in Ivory Coast]. / Evaluation de l'état vaccinal contre l'hépatite B et portage de l'Ag HBs chez les militaires Béninois en mission en Côte d'Ivoire.

INTRODUCTION: This study aims to determine the rate of anti-hepatitis B virus coverage (anti-HBV) and the prevalence of Ag HBs among Beninese soldiers participating in military missions in Ivory Coast. METHODS: We conducted a cross-sectional study within the Beninese battalion based in Anankouakouté in the Ivory Coast. The company's soldiers were administered interview-based questionnaire during a health education session. It focused on socio-demographic data, risk factors for infection and a history of vaccination against hepatitis B. Samples were analyzed for Ag HBs and HBS antibodies. Sodiers positive for AgHBs underwent complementary tests (ALT, HBeAg, anti-HBe antibody, IgM anti-HBc antibody and HBV DNA using PCR). RESULTS: One hundred seventy-five soldiers were enrolled in this study (with an average age of 31 years, ranging between 23 and 52 years; sex-ratio 5.73). Protective anti-HB antibody levels were found in 41 soldiers (23.4%). Some soldiers had had B hepatitis and had developed immunity to the virus (25 cases/41) while others had developed immunity after vaccination (16 cases/41). Eighteen soldiers (10.3%) had HBV (HBsAg+) infection. This infection was chronic (IgM anti-HBc - and anti-HBc antibody total + in 18 cases/18). Among the infected soldiers, 4 had elevated aminotransferase levels, 4 were found HBeAg-positive and 4 had elevated viremia levels (HBV DNA >2000IU/ml). CONCLUSION: The prevalence of Ag HBs among Beninese soldiers participating in military missions is high. However, immunization coverage is low. Intervention strategies should be implemented in order to treat subjects who meet the criteria and to vaccinate the unimmunized patients.

Knowledge, attitudes, and behavior among key people involved in the employment of people with epilepsy in southern Benin.

PURPOSE: This study aimed to investigate knowledge, attitudes, and behavior among individuals working to achieve, or promote, the employment and retention in employment of people with epilepsy (PWE) in Benin. METHODS: We interviewed 300 subjects using a self-administered questionnaire. RESULTS: Knowledge: 93% had heard of epilepsy; 8.8% had at least one person with epilepsy (PWE) in their family; and 67.3% had witnessed a person having epileptic seizures. Attitudes and behavior: 95.3% and 95%, respectively, expressed their views that PWE should be able to enter mainstream education and that PWE should marry; 76.4% considered PWE equal to themselves; and 28.6% reported they would not hire a PWE. We found some associations between demographic characteristics and knowledge, attitudes, and behavior among respondents. A few unhelpful aspects of knowledge, attitudes, and behavior were identified. CONCLUSIONS: Our study showed a fairly high level of accurate knowledge of epilepsy, but some misperceptions and unhelpful attitudes and practices toward PWE in Benin were noted. This study's findings can be used to help plan appropriate strategies based on correcting misperceptions concerning inclusion and retention in employment of PWE in Benin.

Characterization of the novel HLA-C*16:07:02 allele in a family of Benin origin.

The novel allele HLA-C*16:07:02 differs from HLA-C* 16:07:01 by a silent nucleotide substitution at codon 220 (TAC → TAT).

Dengue virus infections in travellers returning from Benin to France, July-August 2010.

In July and August 2010, two cases of dengue fever were diagnosed in travellers returning from Benin to France. These two cases exemplify that dengue fever should be considered in febrile travellers, even those returning from areas where the infection is not usual.

Sociocultural and psychological features of perceived stigma reported by people with epilepsy in Benin.

PURPOSE: Stigma is a major burden of epilepsy. In sub-Saharan Africa the few studies that addressed epilepsy stigma emphasize enacted, rather than perceived, stigma. This inattention may compromise clinical management and delay help seeking, thereby contributing to the treatment gap. We assessed perceived stigma and identified sociocultural and psychological factors explaining greater stigma among people with epilepsy (PWE) in Benin. METHODS: PWE included in this study were ascertained using a door-to-door survey in the general population in a Beninese rural area. We applied both qualitative and quantitative research methods to assess stigma and patient's experience and beliefs. An Explanatory Model Interview Catalogue (EMIC) and verbally administered questionnaires provided data for demographic, clinical, and sociocultural features. Sociocultural features were evaluated in terms of illness-related experience and sociocultural representations of epilepsy. Depression and anxiety were also screened. RESULTS: Eighty PWE were included. About 68.7% reported feeling stigmatized. Multivariate regression revealed that factors independently associated with perceived stigma were experience of social isolation (p < 0.001), experience of marital problems (p < 0.01), and presence of anxiety disorder (p < 0.01). DISCUSSION: Perceived stigma is an important issue in epilepsy in Benin. Social factors seem to be more influential than sociocultural representation of epilepsy. Insofar as research is needed in other African countries to determine the nature and relevant features of stigma to improve treatment and control.

Ethnic differences in the frequency of the cardioprotective C679X PCSK9 mutation in a West African population.

PCSK9 is a liver-secreted blood protein that promotes the degradation of low-density lipoprotein receptors, leading to reduced hepatic uptake of plasma cholesterol. Nucleotide variations in its gene have been linked to hypo- and hyper-cholesterolemia. Two nonsense mutations, Y142X and C679X, are associated to lifelong hypocholesterolemia and a remarkable protection against coronary heart disease (CHD) in African Americans. The aim of this study was to determine the frequency of these cardioprotective mutations in West Africans. Subjects (n = 520) from different ethnic groups were recruited in Burkina-Faso, Benin, and Togo. Only the C679X mutation was detected. All carriers were heterozygous. The overall heterozygosity frequency was 3.3%. It varied significantly among ethnic groups, ranging from 0% to 6.9%. The overall high frequency of the cardioprotective C679X mutation in Africa may contribute to the lower incidence of CHD on this continent. The interethnic frequency differences may reflect historical settlement and migration patterns in the region, possibly combined with positive selection for the mutation driven by yet-unknown environmental factors.

Eosinofilia en inmigrante africano asintomático / Asymptomatic eosinophilia in an African immigrant

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BetaS-haplotypes in sickle cell anemia patients from Salvador, Bahia, Northeastern Brazil.

BetaS-Globin haplotypes were studied in 80 (160 betaS chromosomes) sickle cell disease patients from Salvador, Brazil, a city with a large population of African origin resulting from the slave trade from Western Africa, mainly from the Bay of Benin. Hematological and hemoglobin analyses were carried out by standard methods. The betaS-haplotypes were determined by PCR and dot-blot techniques. A total of 77 (48.1%) chromosomes were characterized as Central African Republic (CAR) haplotype, 73 (45.6%) as Benin (BEN), 1 (0.63%) as Senegal (SEN), and 9 (5.63%) as atypical (Atp). Genotype was CAR/CAR in 17 (21.3%) patients, BEN/BEN in 17 (21.3%), CAR/BEN in 37 (46.3%), BEN/SEN in 1 (1.25%), BEN/Atp in 1 (1.25%), CAR/Atp in 6 (7.5%), and Atp/Atp in 1 (1.25%). Hemoglobin concentrations and hematocrit values did not differ among genotype groups but were significantly higher in 25 patients presenting percent fetal hemoglobin (%HbF) > or = 10% (P = 0.002 and 0.003, respectively). The median HbF concentration was 7.54+/-4.342% for the CAR/CAR genotype, 9.88 3.558% for the BEN/BEN genotype, 8.146 4.631% for the CAR/BEN genotype, and 4.180+/-2.250% for the CAR/Atp genotype (P = 0.02), although 1 CAR/CAR individual presented an HbF concentration as high as 15%. In view of the ethnic and geographical origin of this population, we did not expect a Hardy-Weinberg equilibrium for CAR/CAR and BEN/BEN homozygous haplotypes and a high proportion of heterozygous CAR/BEN haplotypes since the State of Bahia historically received more slaves from Western Africa than from Central Africa.

Educational level is associated with condom use within non-spousal partnerships in four cities of sub-Saharan Africa.

BACKGROUND: Rates of condom use in sub-Saharan Africa have remained too low to curb HIV/sexually transmitted disease (STD) epidemics. A better understanding of the main determinants of condom use would aid promotion. METHODS: Cross-sectional population surveys were conducted in four cities in sub-Saharan Africa: Yaoundé, Cameroon; Cotonou, Benin; Ndola, Zambia; and Kisumu, Kenya. In each city, the aim was to interview a random sample of 1000 men and 1000 women aged 15--49 years, including questions on characteristics of non-spousal partnerships in the past 12 months. RESULTS: Data on condom use were available for 4624 non-spousal partnerships. In the four cities, the proportion of partnerships in which condoms were used always or most of the time ranged from 23.8 to 33.5% when reported by men and from 10.7 to 25.9% when reported by women. Based on the reports from men, condom use was associated with higher educational level of the male partner in Yaoundé [adjusted odds ratio (aOR) = 1.76] and Ndola (aOR = 2.94) and with higher educational level of the female partner in Cotonou (aOR = 2.36) and Kisumu (aOR = 2.76). Based on the reports from women, condom use was associated with higher educational level of the female partner in Kisumu (aOR = 2.60) and Ndola (aOR = 4.50) and with higher educational level of the male partner in Yaoundé (aOR = 3.32). Associations with other determinants varied across cities and for men and women. CONCLUSIONS: Education was found to be a key determinant of condom use in all four cities. This suggests that educational level increases response to condom promotion and highlights the need for special efforts to reach men and women with low educational attainment.

[Intramedullary spinal cord sarcoidosis. Case report and review of the literature]. / Neurosarcoïdose intramédullaire inaugurale d'une sarcoïdose systémique. A propos d'un cas et revue de la littérature.

Sarcoidosis is a multisystemic granulomatosis disease of unknown etiology which commonly involves hilary nodes and lungs. Involvement of the nervous system represents 5 to 15% of the cases. We report on a rare case of cervicothoracic spinal cord sarcoidosis in an African man and review the literature on the subject. His only symptoms were those of a subacute myelopathy. On MR-imaging, coexistence of abnormal signal of cervicothoracic spinal cord with mediastinal lymph nodes was suggestive of sarcoidosis, which was confirmed by bronchial biopsies making unnecessary biopsies of the spinal cord lesion. Under corticotherapy both symptoms and radiological abnormalities rapidly regressed. We emphasize the rarity of sarcoidosis exclusively revealed by a myelopathy. We stress the importance of searching other localizations which are easier and safer to biopsy than the spinal cord lesion itself and illustrate the MR appearances of the lesion which are suggestive, however not specific of the disease.

Molecular characteristics of pediatric patients with sickle cell anemia and stroke.

Cerebrovascular accidents (CVA) are serious complications of sickle cell anemia (SS) in children. Factors that predispose children to this complication are not well established. In an effort to elucidate the risk factors associated with CVA in SS, we have determined the alpha-globin genotype and the beta(S) haplotype of children with this complication. Among 700 children with SS followed at Children's Hospital of Michigan, 41 (6%) are on chronic transfusions because of stroke due to cerebral infarction. The mean age of patients with CVA at the time of stroke was 5.6 +/- 3.2 years (mean +/- SD). The male/female ratio was 2/3. Only 8 of 41 patients (19.5%) had one alpha-gene deletion, compared to the reported prevalence of 30% in African-Americans. None of the patients had two alpha-gene deletions, and two (5%) had five alpha-genes. These findings are different than those in our adult patients with SS, where the prevalence of -alpha/-alpha and alphaalphaalpha/alphaalpha is 4% and <2%, respectively. Ten different beta(S)-haplotypes were detected in the patients studied. The majority of the patients (31%) were doubly heterozygous for the Ben/CAR haplotypes followed by Ben/Ben, Ben/Sen, and CAR/CAR haplotypes, respectively. The prevalence of these haplotypes, with the exception of the CAR/CAR haplotype, was higher in females than males. All the patients with CAR/CAR haplotype were males, had four alpha-genes, and ranked third in prevalence. Three patients were heterozygous for the Cameron haplotype. The Cameron and atypical haplotypes were more prevalent than reported in patients with SS at large. The data suggest that CVA in children seems to occur more frequently in females and in patients with certain beta(S) haplotype. alpha-Gene deletion seems to offer a protective effect against this complication. Neonates with four or more alpha-genes whose beta(S) haplotype is Ben/CAR, atypical, or CAR/CAR seem to be at a higher risk for CAV than other patients. A prospective study on a larger group of patients with or without CVA may clarify this issue.

[Spinal cord involvement revealing systemic sarcoidosis]. / Sarcoïdose systémique révélée par une localisation médullaire.

Spinal neurosarcoidosis is rare (0.43 p. 100 of all sarcoidosis) and can be the initial manifestation of the disease. A 43-year-old right handed African man developed a progressive dorsal neck pain, slowly worsened paresthesia weakness in the legs and a gait disturbance. Magnetic resonance imaging (MRI) scan of the cervical and thoracic spinal cord (sagittal T(1)- weighted image) revealed diffuse enlargement of the cord from C2 to T7 with intense intramedullary enhancement from C2 to T3 after administration of contrast material on sagittal T(1)- weighted image. Cranial MRI scan was normal. Radiographs of the chest revealed bilateral symmetric hilar mediastinal lymphadenopathy with no pulmonary infiltrates. Bronchial biopsy demonstrated non caseating granulomas with langerhans giant cells. The serum angiotensin converting enzyme level was elevated. The patient received corticosteroid with good progressive response. His neurologic symptoms improved markedly and twenty months post-treatment MRI showed no abnormality on enhanced T(1)- weighted images. Two years later he had no relapse. Only 6 to 10 p. 100 of patients with neurosarcoidosis have spinal cord involvement, which may account for the first clinical manifestation of the disease. Most patients with neurosarcoidosis have associated extraneurologic abnormalities. The diagnosis is supported usually by extraneurologic biopsies. Spinal cord biopsy needs to be considered on case-by-case basis.

[Hemoglobin beta S haplotype in the Kebili region (southern Tunisia)]. / Etude de l'haplotype beta S de l'hémoglobine dans la région de Kebili (Sud tunisien).

Sickle cell anemia is a monogenic hereditary disease characterized by a mutation in the beta globin gene. Five major haplotypes associated with the beta S mutation have been defined: Benin, Bantu, Senegalian, Camerounian, and Arabo-Indian. Previous studies in northern Tunisia showed that sickle cell anemia was of Benin origin in this region. Patients from the south of Tunisia, mainly from the Kebili region, were not previously concerned. In this study, we have determined the beta S haplotype and evaluated phenotypical expression of the disease in 14 patients from this latter region. The use of four restriction endonucleases having polymorphic sites in the beta globin gene showed that all patients had the Benin haplotype, confirming the Benin origin of sickle cell anemia in Tunisia. This haplotype is associated with an heterogeneous expression of fetal hemoglobin (HbF) with extremes varying from 2.4 to 16.3% and a mean expression rate of 8.16%, which is in accordance with literature data. In spite of the haplotype homogeneity in our patients, clinical heterogeneity was noted. A unique case of alpha-thalassemia could not explain this heterogeneity. In contrast, we found a certain correlation between fetal hemoglobin expression and clinical severity.

Spectrin St Claude, a splicing mutation of the human alpha-spectrin gene associated with severe poikilocytic anemia.

An alpha-spectrin variant with increased susceptibility to tryptic digestion, alpha(II/47), was previously observed in a child with severe, recessively inherited, poikilocytic anemia. The molecular basis of this variant, spectrin St Claude, has now been identified as a splicing mutation of the alpha-spectrin gene due to a T --> G mutation in the 3' acceptor splice site of exon 20. This polypyrimidine tract mutation creates a new acceptor splice site, AT --> AG, and leads to the production of two novel mRNAs. One mRNA contains a 12 intronic nucleotide insertion upstream of exon 20. This insertion introduces a termination codon into the reading frame and is predicted to encode a truncated protein (108 kD) that lacks the nucleation site and thus cannot be assembled in the membrane. In the other mRNA, there is in-frame skipping of exon 20, predicting a truncated (277 kD) alpha-spectrin chain. The homozygous propositus has only truncated 277 kD alpha-spectrin chains in his erythrocyte membranes. His heterozygous parents are clinically and biochemically normal. This allele was identified in 3% of asymptomatic individuals from Benin, Africa.