Leveraging genomic diversity to promote human and animal health

Contains fulltext : 215655.pdf (publisher's version ) (Open Access)Genomic diversity is a driving force influencing human and animal health, and susceptibility to disease. During the Keystone Symposium on Leveraging Genomic Diversity to Promote Human and Animal Health held in Kampala on Lake Victoria in Uganda, we brought together diverse communities of geneticists with primary objectives to explore areas of common interest, joint technological and methodological developments and applications, and to leverage opportunities for cross-learning. We explored translational genomics research in farmed animals and humans, debated the differences in research objectives in high- and low-resourced environments, delved into infectious diseases and zoonoses affecting humans and animals and considered diversity and cultural context at many levels. The 109 participants were from 22 countries (13 in Africa) and included 44 global travel awardees from 9 countries, equal numbers of men and women, of whom 31 were students and 13 senior investigators

Viral metagenomics of aphids present in bean and maize plots on mixed-use farms in Kenya reveals the presence of three dicistroviruses including a novel Big Sioux River virus-like dicistrovirus

Background: Aphids are major vectors of plant viruses. Common bean (Phaseolus vulgaris L.) and maize (Zea mays L.) are important crops that are vulnerable to aphid herbivory and aphid-transmitted viruses. In East and Central Africa, common bean is frequently intercropped by smallholder farmers to provide fixed nitrogen for cultivation of starch crops such as maize. We used a PCR-based technique to identify aphids prevalent in smallholder bean farms and next generation sequencing shotgun metagenomics to examine the diversity of viruses present in aphids and in maize leaf samples. Samples were collected from farms in Kenya in a range of agro-ecological zones. Results: Cytochrome oxidase 1 (CO1) gene sequencing showed that Aphis fabae was the sole aphid species present in bean plots in the farms visited. Sequencing of total RNA from aphids using the Illumina platform detected three dicistroviruses. Maize leaf RNA was also analysed. Identification of Aphid lethal paralysis virus (ALPV), Rhopalosiphum padi virus (RhPV), and a novel Big Sioux River virus (BSRV)-like dicistrovirus in aphid and maize samples was confirmed using reverse transcription-polymerase chain reactions and sequencing of amplified DNA products. Phylogenetic, nucleotide and protein sequence analyses of eight ALPV genomes revealed evidence of intra-species recombination, with the data suggesting there may be two ALPV lineages. Analysis of BSRV-like virus genomic RNA sequences revealed features that are consistent with other dicistroviruses and that it is phylogenetically closely related to dicistroviruses of the genus Cripavirus.Work was funded by a grant from the Sustainable Crop Production Research for International Development programme funded by the UK Biotechnology and Biological Sciences Research Council (BBSRC) with co-funding from the UK Department for International Development, the Bill & Melinda Gates Foundation, the Department of Biotechnology of India’s Ministry of Science and Technology, and the Indian Council of Agricultural Research (BB/J011762/1) and a Global Challenges Research Fund Foundation Award (BB/P023223/1). LAB was funded by a Cambridge BBSRC doctoral training programme studentship

Phenolic content and antioxidant activity of young and mature mango (Mangifera indica) and avocado (Persea americana) leave extracts

Polyphenols are groups of secondary metabolites in plants, known with their various biological activities, including their ability to act as antioxidants. Due to the side effects of the use of synthetic antioxidants on human’s health, the search for natural less toxic compounds has significantly increased. This study was carried out to evaluate the phenolic content and antioxidant activity of young and mature avocado (Persea americana) and mango leaves (Mangifera indica). Different extracts were prepared by maceration in methanol, ethanol, cold and hot water. The phenolic content of the extracts was determined using the Folic-Ciocalteu Method. A total of three antioxidant tests were done on the extracts: the 2, 2-diphenyl-1-picrylhydrazyl test (DPPH test), the Ferric reducing antioxidant power and the Hydroxyl radical scavenging activity. Results of these investigations generally showed that the mature leaves of mango and young leaves of avocado exhibited the highest phenolic and flavonoid contents, as well as the antioxidant activity. They can be recommended as good sources of antioxidants to reduce the damages caused by free radicals and reactive oxygenated species in the body. They can also be recommended as a source of antioxidants for the preservation of oils, food containing lipids and pharmaceutical products

Human Immunodeficiency Virus and Hepatitis C Virus Co-infection in Cameroon: Investigation of the Genetic Diversity and Virulent Circulating Strains

Background: RNA virus infections represent a significant cause of illness and death in vertebrates. Specifically in humans, RNA viruses are responsible for a wide range of acute, chronic, emerging and re-emerging infections. HIV and HCV rank as some of the most severe RNA viruse infections facing Africa. Methods: To determine genotypes and subtypes of HIV and HCV among co-infected patients in Cameroon, viral RNA was isolated from HIV/HCV co-infected individuals, in Douala, Cameroon. A total of 36 HIV/HCV co-infected isolates (22 from volunteer blood donors and 14 from people living with HIV/AIDS not yet on antiretroviral treatment) were analyzed using molecular biology techniques that involved RT-PCR, gene/TOPO cloning, DNA sequencing, and bioinformatics tools for sequence management and analysis. Epidemiological data were examined as well.Results: Results show that HIV strains isolated belong to the circulating recombinant forms CRF02_AG, whereas HCV isolates from Cameroon belong to genotypes 1, 2, and 4. The corresponding HCV subtypes investigated were 1a, 1b, 1c, 2a, 2c, 2k, and 4a. Subtypes 1a and 1b, most frequently found in developed countries, also circulate in Cameroon. Epidemiologic data show that HIV/HCV co-infected patients are older than HIVmono-infected patients.Conclusions: These results indicate that HIV/HCV co-infection represent a significant threat in Cameroon. There is evidence of genetic diversity of HIV and HCV; virulent hepatitis C virus subtypes 1a and 1b circulate in Cameroon. An epidemiological and molecular database on HIV and HCV is necessary for the development of further intervention in Cameroon as an imperative for monitoring disease progression.Key words: HIV; HCV; Co-infection ; Genotypes ; Virulent