Screening of BRCA1 (c.5177_5180delGAAA rs80357867 and c.4986+6T>C rs80358086) and the BRCA2 (c.6445_6446delAT rs80359592) genes for breast cancer prevention in Burkina Faso

BACKGROUND: The objective of this study is to search for mutations in the BRCA1 (c.5177_5180delGAAA and c.4986+6T>C) and BRCA2 genes (c.6445_6446delAT) in a population of women diagnosed with breast cancer.METHODS: This is a case-control study that involved 140 participants, including 70 patients with histologically diagnosed breast cancer and 70 healthy women without breast cancer. Mutations in the BRCA1 (rs80357867, rs80358086) and BRCA2 (rs80359592) genes were tested by real-time PCR. The 95% confidence interval Odds Ratio (OR) was used to estimate the associations between specific genotypes and breast cancer.RESULTS: The study revealed that no mutations were detected for rs80359592. Similarly, no reference allele (TTTC/TTTC) of rs80357867 was found in this study. However, the homozygous double mutant (-/) genotype of this rs80357867 was observed in 11.43% and 1.43% of patients and controls respectively, while 88.57% of patients and 98.57% of controls had a heterozygous deletion (TTTC/-). Concerning rs80358086, 8.57% of the patients had a heterozygous mutation (A/G) with no significantly risk association with occurrence of breast cancer (OR = 6.46; 95% CI: 0.75-55.21; p = 0.11). In addition, this heterozygous mutation was significantly associated with a family history of breast cancer (OR=128; 95% CI: 9.46-1730.93) and breast cancer risk in nonmultiparous women (OR=6; 95% CI: 1-35.90; p= 0.05) but no association with overweight/obesity (OR=1.66; 95% CI: 0.18-15.35; p=1).CONCLUSION: This study shows high frequencies of heterozygous mutation of rs80357867 and rs80358086 from patients. In Burkina Faso, these results could help with early diagnosis of breast cancer in patients

No correlation between the variants of exostosin 2 gene and type 2 diabetes in Burkina Faso population

Recent genome-wide association studies and replication analyses have reported the association of variants of the exostosin- 2 gene (EXT2) and risk of type 2 diabetes (T2D) in some populations, but not in others. This study aimed to characterize the variants rs1113132, rs3740878 and rs11037909 of EXT2 and to determine the existence of a possible correlation with T2D in Burkina Faso. It is a case-control study undertaken in Burkina Faso in the city of Ouagadougou at the Hospital of Saint Camille of Ouagadougou from December 2014 to June 2015. It relates to 121 type 2 diabetes cases and 134 controls. The genotyping of these polymorphisms was done by real-time PCR using the allelic exclusion method with TaqMan probes. The minor allele frequencies (MAFs) was almost identical in diabetic and control subjects for the all three Single Nucleotide Polymorphisms (SNPs) with no statistical significance, p0.05: rs1113132 (OR=0.89; p=0.82); rs11037909 (OR=0.89; p=0.74) and rs3740878 (OR=1.52; p=0.42). None of the three polymorphisms studied was associated with the risk of DT2. However, an association between the BMI, age and type 2 diabetes was noted. The variants of EXT2 would not be associated to the risk of T2D in the African black population of Burkina Faso

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Characteristics of HIV-2 and HIV-1/HIV-2 Dually Seropositive Adults in West Africa Presenting for Care and Antiretroviral Therapy: The IeDEA-West Africa HIV-2 Cohort Study.

HIV-2 is endemic in West Africa. There is a lack of evidence-based guidelines on the diagnosis, management and antiretroviral therapy (ART) for HIV-2 or HIV-1/HIV-2 dual infections. Because of these issues, we designed a West African collaborative cohort for HIV-2 infection within the framework of the International epidemiological Databases to Evaluate AIDS (IeDEA).We collected data on all HIV-2 and HIV-1/HIV-2 dually seropositive patients (both ARV-naive and starting ART) and followed-up in clinical centres in the IeDEA-WA network including a total of 13 clinics in five countries: Benin, Burkina-Faso Côte d'Ivoire, Mali, and Senegal, in the West Africa region.Data was merged for 1,754 patients (56% female), including 1,021 HIV-2 infected patients (551 on ART) and 733 dually seropositive for both HIV-1 and HIV 2 (463 on ART). At ART initiation, the median age of HIV-2 patients was 45.3 years, IQR: (38.3-51.7) and 42.4 years, IQR (37.0-47.3) for dually seropositive patients (p = 0.048). Overall, 16.7% of HIV-2 patients on ART had an advanced clinical stage (WHO IV or CDC-C). The median CD4 count at the ART initiation is 166 cells/mm(3), IQR (83-247) among HIV-2 infected patients and 146 cells/mm(3), IQR (55-249) among dually seropositive patients. Overall, in ART-treated patients, the CD4 count increased 126 cells/mm(3) after 24 months on ART for HIV-2 patients and 169 cells/mm(3) for dually seropositive patients. Of 551 HIV-2 patients on ART, 5.8% died and 10.2% were lost to follow-up during the median time on ART of 2.4 years, IQR (0.7-4.3).This large multi-country study of HIV-2 and HIV-1/HIV-2 dual infection in West Africa suggests that routine clinical care is less than optimal and that management and treatment of HIV-2 could be further informed by ongoing studies and randomized clinical trials in this population

Rare predicted loss-of-function variants of type I IFN immunity genes are associated with life-threatening COVID-19

BackgroundWe previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15-20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in similar to 80% of cases.MethodsWe report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded.ResultsNo gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5-528.7, P=1.1x10(-4)) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR=3.70[95%CI 1.3-8.2], P=2.1x10(-4)). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR=19.65[95%CI 2.1-2635.4], P=3.4x10(-3)), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR=4.40[9%CI 2.3-8.4], P=7.7x10(-8)). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD]=43.3 [20.3] years) than the other patients (56.0 [17.3] years; P=1.68x10(-5)).ConclusionsRare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old