Common and Founder Mutations for Monogenic Traits in Sub-Saharan African Populations

2018 ◽  
Vol 19 (1) ◽  
pp. 149-175
Author(s):  
Amanda Krause ◽  
Heather Seymour ◽  
Michèle Ramsay
Keyword(s):  
Molecular Genetic ◽  
Black Families ◽  
Oculocutaneous Albinism ◽  
Sub Saharan Africa ◽  
Founder Mutations ◽  
Monogenic Diseases ◽  
African Populations ◽  
Clinical Consequences ◽  
Sub Saharan ◽  
Almost All

This review highlights molecular genetic studies of monogenic traits where common pathogenic mutations occur in black families from sub-Saharan Africa. Examples of founder mutations have been identified for oculocutaneous albinism, cystic fibrosis, Fanconi anemia, and Gaucher disease. Although there are few studies from Africa, some of the mutations traverse populations across the continent, and they are almost all different from the common mutations observed in non-African populations. Myotonic dystrophy is curiously absent among Africans, and nonsyndromic deafness does not arise from mutations in GJB2 and GJB7. Locus heterogeneity is present for Huntington disease, with two common triplet expansion loci in Africa, HTT and JPH3. These findings have important clinical consequences for diagnosis, treatment, and genetic counseling in affected families. We currently have just a glimpse of the molecular etiology of monogenic diseases in sub-Saharan Africa, a proverbial “ears of the hippo” situation.

scholarly journals Motor Neuron Diseases in Sub-Saharan Africa: The Need for More Population-Based Studies

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Emmanuel Quansah ◽  
Thomas K. Karikari
Keyword(s):  
Motor Neuron ◽  
Muscular Atrophy ◽  
Clinical Care ◽  
Treatment Options ◽  
Molecular Genetic ◽  
Population Based ◽  
Sub Saharan Africa ◽  
Motor Neuron Diseases ◽  
African Populations ◽  
Sub Saharan

Motor neuron diseases (MNDs) are devastating neurological diseases that are characterised by gradual degeneration and death of motor neurons. Major types of MNDs include amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA). These diseases are incurable, with limited disease-modifying treatment options. In order to improve MND-based biomedical research, drug development, and clinical care, population-based studies will be important. These studies, especially among less-studied populations, might identify novel factors controlling disease susceptibility and resistance. To evaluate progress in MND research in Africa, we examined the published literature on MNDs in Sub-Saharan Africa to identify disease prevalence, genetic factors, and other risk factors. Our findings indicate that the amount of research evidence on MNDs in Sub-Saharan Africa is scanty; molecular and genetics-based studies are particularly lacking. While only a few genetic studies were identified, these studies strongly suggest that there appear to be population-specific causes of MNDs among Africans. MND genetic underpinnings vary among different African populations and also between African and non-African populations. Further studies, especially molecular, genetic and genomic studies, will be required to advance our understanding of MND biology among African populations. Insights from these studies would help to improve the timeliness and accuracy of clinical diagnosis and treatment.

scholarly journals Multiple Mammarenaviruses Circulating in Angolan Rodents

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 982
Author(s):  
Jana Těšíková ◽  
Jarmila Krásová ◽  
Joëlle Goüy de Bellocq
Keyword(s):  
Geographical Area ◽  
Sub Saharan Africa ◽  
Virus Diversity ◽  
High Prevalence ◽  
Biogeographical Regions ◽  
Sub Saharan ◽  
Rodent Community ◽  
High Virus ◽  
Almost All ◽  
Virus Genomes

Rodents are a speciose group of mammals with strong zoonotic potential. Some parts of Africa are still underexplored for the occurrence of rodent-borne pathogens, despite this high potential. Angola is at the convergence of three major biogeographical regions of sub-Saharan Africa, each harbouring a specific rodent community. This rodent-rich area is, therefore, strategic for studying the diversity and evolution of rodent-borne viruses. In this study we examined 290 small mammals, almost all rodents, for the presence of mammarenavirus and hantavirus RNA. While no hantavirus was detected, we found three rodent species positive for distinct mammarenaviruses with a particularly high prevalence in Namaqua rock rats (Micaelamys namaquensis). We characterised four complete virus genomes, which showed typical mammarenavirus organisation. Phylogenetic and genetic distance analyses revealed: (i) the presence of a significantly divergent strain of Luna virus in Angolan representatives of the ubiquitous Natal multimammate mouse (Mastomys natalensis), (ii) a novel Okahandja-related virus associated with the Angolan lineage of Micaelamys namaquensis for which we propose the name Bitu virus (BITV) and (iii) the occurrence of a novel Mobala-like mammarenavirus in the grey-bellied pygmy mouse (Mus triton) for which we propose the name Kwanza virus (KWAV). This high virus diversity in a limited host sample size and in a relatively small geographical area supports the idea that Angola is a hotspot for mammarenavirus diversity.

scholarly journals Continuing high levels of HIV diagnoses in men who have sex with men in the United Kingdom

2008 ◽  
Vol 13 (14) ◽  
pp. 3-4
Author(s):  
B Rice ◽  
A Nardone ◽  
N Gill ◽  
V Delpech
Keyword(s):  
United Kingdom ◽  
Confidence Intervals ◽  
Sub Saharan Africa ◽  
Newly Diagnosed ◽  
The United Kingdom ◽  
Reporting Delays ◽  
Sub Saharan ◽  
Sex With Men ◽  
The Uk ◽  
Almost All

The latest HIV data for 2007 has recently been published for the United Kingdom (UK). During the year, an estimated 6,840 (95% confidence intervals 6,600-7,050) persons (adjusted for reporting delays) were newly diagnosed with HIV in the UK. This represents a 12% decline from a peak of new HIV diagnoses reported in 2005 (7,800). Almost all this decline in new HIV diagnoses was in HIV-infected heterosexuals from sub-Saharan Africa who were probably infected in their country of origin.

scholarly journals Factors associated with oral cavity cancers in Sub-Saharan Africa: Summary of the literature

2021 ◽  
Vol 1 (2) ◽  
pp. 34-41
Author(s):  
A Dieng ◽  
AD Faye ◽  
MM Ndiaye ◽  
G Diop ◽  
A Bouazé ◽  
...  
Keyword(s):  
Oral Cavity ◽  
Public Health Problem ◽  
Epidemiological Data ◽  
Sub Saharan Africa ◽  
Factors Associated ◽  
Manual Search ◽  
African Populations ◽  
Localization Strategy ◽  
Sub Saharan ◽  
Oral Cavity Cancers

INTRODUCTION: Oral cavity cancers are now a public health problem according to WHO epidemiological data. There are several risk factors or factors associated with cancers of the oral cavity but they vary according to geographic regions. OBJECTIVE: The objective of this study was to identify factors associated with cancers of the oral cavity in Sub-Saharan African populations through a systematic literature review. METHODOLOGY: Using the data available for the period from January 1980 to December 2019, a synthesis of the literature was carried out. The literature localization strategy included an electronic search of the MEDLINE, EMBASE and GOOGLE SCHOLAR databases from 1980 to 2019 and a manual search of the list of references of articles identified by snowballing. The data were extracted independently by two researchers on an Excel© spreadsheet. Parameters collected from each study were author, country, type of study, period of study, size, age, gender, and factors studied. RESULTS: Out of 1,318 articles found, 24 were selected. The data contained 17,290 patients including 8,229 men, i.e. a male / female sex-ratio of 0.91. Factors studied were tobacco, alcohol, diet, infection, genetics and social factors. CONCLUSION: The results reported showed that several factors are associated with the occurrence of oral cavity cancers in Sub-Saharan Africa. There is a need to conduct further studies with more structured methodologies for more convincing results.

scholarly journals Estimating the timing of multiple admixture pulses during local ancestry inference

2018 ◽  
Author(s):  
Paloma Medina ◽  
Bryan Thornlow ◽  
Rasmus Nielsen ◽  
Russell Corbett-Detig
Keyword(s):  
Biological Process ◽  
Genetic Material ◽  
Simulated Data ◽  
Sub Saharan Africa ◽  
African Populations ◽  
Fundamental Biological Process ◽  
Admixed Population ◽  
Sub Saharan ◽  
Local Ancestry Inference ◽  
Admixture Event

ABSTRACTAdmixture, the mixing of genetically distinct populations, is increasingly recognized as a fundamental biological process. One major goal of admixture analyses is to estimate the timing of admixture events. Whereas most methods today can only detect the most recent admixture event, here we present coalescent theory and associated software that can be used to estimate the timing of multiple admixture events in an admixed population. We extensively validate this approach and evaluate the conditions under which it can succesfully distinguish one from two-pulse admixture models. We apply our approach to real and simulated data of Drosophila melanogaster. We find evidence of a single very recent pulse of cosmopolitan ancestry contributing to African populations as well as evidence for more ancient admixture among genetically differentiated populations in sub-Saharan Africa. These results suggest our method can quantify complex admixture histories involving genetic material introduced by multiple discrete admixture pulses. The new method facilitates the exploration of admixture and its contribution to adaptation, ecological divergence, and speciation.

Malaria

2019 ◽  
Author(s):  
Angelina Jayakumar ◽  
Zahir Osman Eltahir Babiker
Keyword(s):  
Southeast Asia ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Parasitic Infection ◽  
Sub Saharan Africa ◽  
Anopheline Mosquito ◽  
Sub Saharan ◽  
The Uk ◽  
Almost All ◽  
Human Infections

Malaria is a tropical parasitic infection of the red blood cells caused by the protozoal species Plasmodium falciparum, P. vivax, P. ovale, P. malariae, and P. knowlesi. It is transmitted through the bite of the female Anopheles mosquito. The average incubation period is twelve to fourteen days. Congenital and blood-borne transmissions can also occur. P. falciparum and P. vivax account for most human infections but almost all deaths are caused by P. falciparum, with children under five years of age bearing the brunt of morbidity and mortality in endemic countries. P. falciparum is dominant in sub-Saharan Africa whereas P. vivax predominates in Southeast Asia and the Western Pacific. P. ovalae and P. malaria are less common and are mainly found in sub-Saharan Africa. P. knowlesi primarily causes malaria in macaques and is geographically restricted to southeast Asia. While taking a blood meal, the female anopheline mosquito injects motile sporozoites into the bloodstream. Within half an hour, the sporozoites invade the hepatocytes and start dividing to form tissue schizonts. In P. vivax and P. ovale, some of the sporozoites that reach the liver develop into hypnozoites and stay dormant within the hepatocytes for months to years after the original infection. The schizonts eventually rupture releasing daughter merozoites into the bloodstream. The merozoites develop within the red blood cells into ring forms, trophozoites, and eventually mature schizont. This part of the life cycle takes twenty-four hours for P. knowlesi; forty-eight hours for P. falciparum, P. vivax, P. ovale; and seventy-two hours for P. malariae. In P. vivax and P. ovale, some of the sporozoites that reach the liver develop into hypnozoites and stay dormant within the hepatocytes for months to years after the original infection. The hallmark of malaria pathogenesis is parasite sequestration in major organs leading to cytoadherence, endothelial injury, coagulopathy, vascular leakage, pro-inflammatory cytokine production, and tissue inflammation. Malaria is the most frequently imported tropical disease in the UK with an annual case load of around 2000. P. falciparum is the predominant imported species, and failure to take chemoprophylaxis is the commonest risk factor.

scholarly journals Finnish Official Development Aid for Sexual and Reproductive Health and Rights in Sub-Saharan Africa

2010 ◽  
pp. 143-170
Author(s):  
Riikka Shemeikka
Keyword(s):  
Reproductive Health ◽  
Development Policy ◽  
Sexual And Reproductive Health ◽  
Health Sector ◽  
Development Aid ◽  
Sub Saharan Africa ◽  
Sub Saharan ◽  
And Gender ◽  
Almost All ◽  
Hiv Aids

Finland is one of the donor countries that is most supportive in family planning (FP), Sexual and Reproductive Health and Rights (SRHR) and gender issues. This study examines Finnish ODA for FP and SRHR: its decision-making structure, other stakeholders and funding levels. Data consists of documents from the Ministry for Foreign Affairs (MFA) and interviews conducted at the MFA and with other experts. While Parliament decides on the overall level of ODA funding, the Minister for Foreign Trade and Development has considerable autonomy. Other stakeholders such as the All-Party Parliamentary Group on Population and Development and the Family Federation of Finland (Vestliitto) engage in advocacy work and have influenced development policy. Although the Development Policy 2007 mentions the importance of health and SRHR issues and HIV/AIDS is a cross-cutting issue, interviewees stated that the importance of health and SRHR in ODA has declined and that the implementation of cross-cutting issues is challenging. Multilateral funding for UNFPA, UNAIDS and GFATM, and thus the proportion of SRHR funding within the health sector, is however currently rising. Funding for population-related activities has increased and represented 4.8% of Finlands total ODA in 2009. Almost all of this funding is directed towards basic reproductive health and HIV/AIDS issues and the majority is directed through multilateral channels (78% in 2009), mainly UNFPA and UNAIDS. IPPF, Ipas and Marie Stopes International also receive support.

French coopération in the field of education (1960–1980): a story of disillusionment

2013 ◽  
pp. 120-134 ◽  
Author(s):  
Samy Mesli
Keyword(s):  
Early Years ◽  
Sub Saharan Africa ◽  
Cultural Dimension ◽  
African Continent ◽  
Francophone Africa ◽  
Fifth Republic ◽  
Secondary Sector ◽  
African Populations ◽  
Sub Saharan ◽  
Physical Construction

Sami Mesly investigates the cultural dimension of continuities between France and various states of ‘Francophone Africa’, as expressed through the co-operation agreements between the independent governments and the French state under the Fifth Republic. These latter guaranteed, initially, a steady exchange between the partners in the field of education. As France’s former colonial territories in sub-Saharan Africa were suddenly confronted with a greatly reduced public budget, French financial help was crucial, in the early years after independence, both for the physical construction of a school infrastructure and for the deployment of thousands of coopérants who became an important part of the staff in African schools. As late as the early 1980s, this French presence remained very significant. It spanned the whole of school education, including the primary and secondary sector, technical education, and higher education (French funding was instrumental in the creation of African universities). Mesly points out that while it is obvious that the French effort has made a major contribution to the growth of the education sector on the African continent, French aid in education offers nevertheless an ambivalent picture. The programmes implemented were poorly adapted to local realities, which in the end led to the installation of a system conditioned by the French view of African populations and not by local needs.

scholarly journals Remote Teaching of Histopathology Using Scanned Slides via Skype Between the United Kingdom and Nigeria

2017 ◽  
Vol 141 (2) ◽  
pp. 298-300 ◽  
Author(s):  
Olorunda Rotimi ◽  
Nnamdi Orah ◽  
Abeer Shaaban ◽  
Adetola O. Daramola ◽  
Fatimah B. Abdulkareem
Keyword(s):  
Cost Effective ◽  
Sub Saharan Africa ◽  
Web Based ◽  
Tertiary Institutions ◽  
Face To Face ◽  
Resource Limited ◽  
Interactive Lectures ◽  
Sub Saharan ◽  
Almost All ◽  
Pathology Teaching

Context.—Web-based learning is a major component of distance education. Objective.—To explore Web-based applications for pathology teaching in resource-limited sub-Saharan Africa. Design.—The participants were consultant pathologists and trainees drawn from tertiary institutions in Nigeria. They viewed the digital slides via the Leeds virtual pathology Web site, after which, interactive lectures were given via Skype (Skype Communications, Luxembourg City, Luxembourg). Questionnaires were administered via SurveyMonkey (Palo Alto, California) to all participants of 12 sessions between 2014 and 2015. Results.—Nine consultant pathologists and 33 trainees participated in this survey. Of all respondents, 29 (69%) thought it was fairly easy to navigate the system, 11 (26.2%) thought it was easy, whereas 2 (4.8%) felt it was difficult. In addition, 26 respondents (61.9%) found it fairly easy to make a make a diagnosis, 13 (31%) thought it was easy, and 3 (7.1%) noted that it was difficult. Twenty-four respondents (57.1%) had a fairly smooth user experience, 12 (28.6%) experienced occasional crashes, whereas 6 (14.3%) reported a smooth experience. Almost all (41 of 42; 97.6%) respondents felt the pathology teaching was beneficial to their local pathology practice, and all (100%) indicated the need for additional, similar sessions. Conclusion.—The beneficial applications of Internet-based lectures make them a viable, cheaper, and cost-effective alternative to face-to-face lectures in our environment.

scholarly journals Kalahari Wildfires Drive Continental Post-Fire Brightening in Sub-Saharan Africa

2019 ◽  
Vol 11 (9) ◽  
pp. 1090
Author(s):  
Michael V. Saha ◽  
Paolo D’Odorico ◽  
Todd M. Scanlon
Keyword(s):  
Energy Budget ◽  
Land Surface ◽  
Regional Climate ◽  
Sub Saharan Africa ◽  
Continental Scale ◽  
Object Based ◽  
Negative Surface ◽  
Sub Saharan ◽  
Sahel Region ◽  
Almost All

Fire can induce long-lived changes to land-surface albedo, an important aspect of the Earth’s energy budget, but the temporal evolution of these anomalies is poorly understood. Due to the widespread presence of fire in Africa, this represents uncertainty in the continental energy budget, which has important implications for regional climate and hydrologic cycling. In this study, we present the first object-based accounting of albedo anomalies induced by larger (>1 km2) individual wildfires in sub-Saharan Africa. We group spatially contiguous wildfire pixels into fire objects and track the albedo anomaly for five years after the burn. We find that albedo anomalies all have the same general temporal signature: An immediate, brief period of darkening followed by persistent brightening. The strongest brightening is found in the Kalahari region while more intense and long-lived initial darkening is found in the Sahel region. The average southern hemisphere albedo anomaly is +1.50 × 10−3 in the year following wildfire, representing a statistically significant negative surface energy balance forcing on a continental scale. This study challenges an existing paradigm surrounding the physical effects of fire on the landscape. Our results suggest that models of albedo that assume a darkening and recovery to baseline are overly simplistic in almost all circumstances. Furthermore, the presumption that immediate darkening is the only meaningful effect on albedo is incorrect for the majority of the African continent.

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