Utilizing Genomics in genetic improvement Molecular genetics as a tool in wildlife breeding, management and conservation (An African Buffalo case study) Ben Greyling ARC-API, Irene
Menu Role of Mol. Gen. in wildlife management/conservation/breeding The ABC of DNA The African buffalo: A case study Genomics: Where do we stand? The Cattle model: from genetic variation, to marker assisted selection to quantitative variation Cape buffalo – recent developments
Primary objective of conservation and management To protect diversity, ensure sustainable use of the resource Driving forces: need to qualify and quantify Role of Mol tools: Supply baseline info Levels of genetic variation, inbreeding Pop structure – genetic distances/assignment? Gene flow between populations? Effective population size vs. census size Admixture (Genomics..) Relationship between variation and fitness/adaptation Gene regulation/expression under environmental control
More applications… Forensics and traceability: Individual ID Parentage verification (selection and management tool) Hybrid identification Genomics: Quantitative variation – from genotype to phenotype Epigenetics: Environments effect on genes - heritable trait expression..
… AACGTGTTGACGCCGTAATGCATAAT CTHISWILLEVENTUALLYDRIVEYOUC RAZYCGCTAGCCTTCGGCAATC... The value of Mol Gen tools: Making sense of “useless information”
A A C G C T T A G C T A G C T C A T T G C G A A T C G A T C G A G T T insertion deletion Point mutation (SNP) letters per cell…
African buffalo: A major role player in our ecosystems/metapopulation Largest populations confined to conservancies Model species with regard to pop. dynamics - factors affecting it Genetic variation, structure, gene flow, disease status, etc. Contributed immensely to conservation and management strategies
Case studies: Population structure KNP vs. HiP 99% accurate assignment of individuals to pops due to genetic distance
Case studies: Genetic variation Periods of low N e for some populations in SA: ?? sustainability of genetic variation ?? compromised adaptation in response to changing environment? Example: Genetic erosion in HiP: 1% per year
East vs. southern African subpopulations? Little genetic differentiation East/southern African population a separate management unit, differ substantially from central/west African lineage Substantial variation in both sub-populations
Gene expression/regulation: The Y-Chromosome Its raining men Environment and body condition: switch on/switch off… Sex ratio distorted: more males in the wet season Particular genotypes dominate depending on environment (season) – affect sex ratio Sex ratio and BTB-link?
Heterozygote-fitness-correlation (HFC) Low genetic variation = low body condition – affect genes on the “Y” Bad genes expressed in southern KNP, link to BTB, what the Y is going on?…. Females can also affect sex ratio… Epigenetic factors? BTB susceptibility may have an epigenetic link – heritable..
Ranches: management-scenario’s Small populations, restricted gene flow Controlled breeding (non-random mating) Fragmented populations and “lines” Breeding and selection among “lines”, e.g. Addo-Lowveld Preference for market-desired phenotypes
Potential consequences of ranching Reduction in genetic variation (inbreeding?) Increase in frequency of deleterious alleles Loss of adaptive genes/fitness disease resistance, reproduction, growth etc. Reduction in effective pop size – sustainability of variation? Admixture – potential outbreeding depression Compromised adaptability
Genomics to the rescue: Linking the DNA code to performance and phenotype (amongst others…) SNP vs. full genome sequences – from a good amount of info to a desired amount of info Powerful tools to address needs of wildlife industry Substantially applied to livestock Quantitative genetics: Selection tool for superior genetics Fast track genetic improvement
Genomics for buffalo? 3K SNP panel already developed identified using next generation sequencing technology Projects in pipeline using the 3K panel = more powerful approach Buffalo and quantitative genetics: Breeding values on the horizon? Scope for genomic breeding values…
Requirements for Genomics: Accurate pedigrees Phenotypic records Reference populations DNA (SNP) profiles Test populations
The future is now with this technology Are we ready to adopt?