ANTH 350 Lecture Notes - Lecture 13: Tay–Sachs Disease, Genetic Drift, Linkage Disequilibrium
Document Summary
Subpopulation derived from a small number of individual isolated due to founder effect that stay isolated. Isolating factors: migration and settlement of remote territory, warm, famine, infectious disease, environmental disruption, social or cultural factors. Populations isolates often face similar/same environmental factors: population isolates and subisolates. Population isolates can branch and develop independently. Close proximity, common origin do not imply identical evolution. May have more than one founder effect and multiple bottleneck. May be regional sub-isolates: linkage disequilibrium. Non random association of alleles at different loci in a particular population. Occurs when the association between different alleles in higher/ lower than we would expect if gene locus was independent and randomly associated. Iso pop ld tends to extend over longer distances, intervals for older isolates and shorter ones for younger ones: founder effect and genetic disorders in ashkenazi jews. Gene flow reduced due to cultural, religious reasons. Tay sachs disease- results in destruction of nerve cells in brain and spinal chord.
