群体遗传学第7章 群体遗传变异.pptx

Chapter7

GeneticVariationinPopulations

PopulationGenetics群体遗传学Populationgeneticsisthestudyofthedistributionofgenesinpopulationsandofhowthefrequenciesofgenesandgenotypesaremaintainedorchanged.以群体为单位，研究群体内的遗传结构及其变化规律的遗传学分支学科。2

WewilldiscussGeneticDiversityinHumanPopulationsGenotypes,GeneFrequenciesandPhenotypesTheHardy-WeinbergLawFrequencyofX-LinkedGenesandGenotypesFactorsthatDisturbHardy-WeinbergEquilibrium3

MendelianPopulation孟德尔群体AReproductivecommunityofindividualswhichshareinacommongenepool(Dobzhansky1950).能相互交配和繁殖的个体群，他们共享一个基因库。GenePool:acollectionofalltheallelesataparticularlocusfortheentirepopulation.Groupsofindividualsanytwoofwhichhaveequalprobabilityofmatingandproducingoffspring(Wright,1943).4

GeneticDiversityinHumanPopulations

Alleles---forGeneticdiseaseLocus:ParticularchromosomallocationAlleles:DifferentversionsofaparticularDNAsequenceatlocusSelectivelyneutralgeneticmarkersGeneticpolymorphism5

GeneticDiversityinHumanPopulationsFactorsthataffectallelesandgenotypesfrequenciesGeneticfactorsMutationReproductionEnvironmentalandsocietalfactorsFoundereffect奠基者效应Geneticdrift遗传漂变Selection选择（自然或人为）6

WewilldiscussGeneticDiversityinHumanPopulationsGeneFrequencies,PhenotypesandGenotypesTheHardy-WeinbergLawFrequencyofX-LinkedGenesandGenotypesFactorsthatDisturbHardy-WeinbergEquilibrium7

Phenotypes,GenotypesandGeneFrequenciesGenotypeFrequency?AlleleFrequencyAlleleFrequency?GenotypeFrequencyGenotype?phenotypes?8

GeneFrequency基因频率Allelefrequencytheproportionofallallelesatonegenelocusthatareofonespecifictypeinapopulation.一个群体中，某类等位基因的数量占该基因座上全部等位基因的比率。9

GeneFrequencyTherelativefrequenciesofvariousallelesforaparticularlocusshouldad