Kemp, Stephen J.

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• Vision for livestock genetics in Africa• Steve Kemp, ILRIAnimal Genetic Research for Africa (Biosciences for Farming in Africa), Nairobi, 10-11 September 2015Genetic selection, interacting with environment, drives ‘improvement’-1000010002000300040005000600070001950 1960 1970 1980 1990 2000 2010YearChange in milk yield (kg)(Source: http://aipl.arsusda.gov/eval/summary/trend.cfm)Changes in milk yields of US Holstein cowsMean phenotype (P), breeding value (A) and environmental effects (E = A - P).Results relative to 1957 base (mean yield 5859kg). APEIn the industrial world genetics has driven dramatic improvements in productivity• Homogeneous environments  (systems, markets, health, regulations, policies…….)• Homogeneous genetics (a handful of well defined breeds)• Superb data recording driving selection schemesAchieving genetic gain in developing countries – the same biological rules but different environmentsWe must take account of the realities of small-scale livestock producers. Diversity of:• Environment• Climate• Feeds available• Endemic diseases• Local market context• Infrastructure• InstitutionsAchieving genetic gain in developing countries – the same biological rules but different environmentsWe must take account of the realities of small-scale livestock producers. Diversity of:• Environment• Climate• Feeds available• Endemic diseases• Local market context• Infrastructure• InstitutionsNo data systems to inform selection. No infrastructure to manage selection.Genotype data is cheap and easy to obtain. Phenotype data remains a problem.Can we skip a generation of technology? • Fast, light, cheap performance data harvesting. • Cheap sensors, mobile platforms, crowd sensing…..• Simultaneously providing management information to the farmer and performance data to the breeder.Diversity of environments has created diversity of genetics. Let’s not discard it.African Trypanosomiasis• Caused by extracellular protozoan parasites –Trypanosoma• Transmitted between mammals by Tsetse flies (Glossina sp.)• Prevalent in 36 countries of sub-Sahara Africa.In cattle• A chronic debilitating and fatal disease.• A major constraint on livestock and agricultural production in Africa. • Costs US$ 1 billion annually.In human (Human Sleeping Sickness)• Fatal• 60,000 people die every year• Both wild and domestic animals are the major reservoir of the parasites for human infection.African TrypanosomiasisControl and Treatment options for African TrypanosomiasisVector Control (Tsetse Fly)• Using toxic insecticide• Not sustainable• Negative impacts on environmentVaccine• Tryps periodically change the major surface antigen – variant surface glycoprotein (VSG) and evade the host immune system.• More than 2 decades, there is no effective vaccine developed.Drug• Drug toxicity and resistance• ExpensiveNew tools allow us to look in new places for sources of variation – including wildlifeComparative gene network and sequence analysis allows to ask new kinds of questions about genomes – eg “what is different about this (group of) species compared to all other mammals”“traditional” linkage mapping requires crosses – so initial discovery is limited to variants within a speciesCow NDama  KFITRRPSLKTLQEKGLIKDQIFGSPLHTLCEREKSTVPRFVKQCIEAVEK Cow Boran  KFITRRPSLKTLQEKGLIKDQIFGSHLHTLCEREKSTVPRFVKQCIEAVEK Human      KFISRRPSLKTLQEKGLIKDQIFGSHLHTVCEREHSTVPWFVKQCIEAVEK Pig        KFITRRPSLKTLQEKGLIKDQIFGSHLHTVCERENSTVPRFVKQCIEAVEK Chicken    KFISRRPSLKTLQEKGLIKDQIFGSHLHLVCEHENSTVPQFVRQCIKAVER Salmon     KFISRRPSMKTLQEKGIIKDRVFGCHLLALCEREGTTVPKFVRQCVEAVEK Time for a new search for variation underlying tropical adaptation and productivity Identify and make use of the genetics underlying natural variation.There has been no systematic search for the genomic basis of adaptation. Because until now we have had no validation tools and no delivery tools.New Genome Editing tools change the landscape.Identify and deliver  variants associated with adaptationGenotypingPhenotypingAdapted & productive livestockGenome editingTargetingData systemsDelivery systemsTLFApoL-I Apolipoprotein Trypanolytic componentHpr Haptoglobin-related protein Facilitates the uptake of TLF by trypanosomes via haptoglobin-hemoglobin receptor.ApoL-I releasedActivated in acidic lysosomeForm membrane pores, resulting in ion disregulation and osmotic imbalanceTrypanosomes lysisEndocytosed into lysosome by TrypanosomesApoA-I Apolipoprotein Found in all HDL subclassesKilling of Tryps by Trypanosome Lytic Factor (TLF)Flagellar pocket of TrypComplete protection from Trypanosomes by baboon ApoL-I in transiently transgenic mice P = < 0.01 Vector vs. treatmentThomson et al PNAS 2009  106:19509-19514 Project StrategyGenomic locus of Baboon apoL-I geneVector constructionValidate the construct in transgenic mouseBovine embryonic fibroblasts (BEF) primary cultureTransfection & screeningapoL-I Transgenic BEFsNuclear TransferTransgenic calvesPhenotypingTrypanosome resistant transgenic Boran bullILRIILRIKenya BoranRoslin InstituteNew York UniversityMichigan State UniversityTumainiA cloned Kenya Boran calf made by SCNT from a Boran embryo fibroblast cell line20The presentation has a Creative Commons licence. You are free to re-use or distribute this work, provided credit is given to ILRI.better lives through livestockilri.orghttp://vimeo.com/74942619 11  minute versionVideo ‘Developing disease-resistant cattle for Africa’http://vimeo.com/74940697 3  minute version

Vision for livestock genetics in Africa

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Vision for livestock genetics in Africa

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