Plan to spend 1 hour minutes on Drift

1. Take drift quiz
2. 50 rats from a large outbred population living aboard of large cruise boat are left on a Pacific island for some reason. The island resources allow only 50 adult rats to survive (population will not grow). Ten mutations are present in single copy each in these 50 rats. After very long time...
   1. What is probability that at least one of these mutations will be fixed (reach frequency of 1.0)?
   2. What is probability that two or more of these mutations will be fixed?
   3. What is chance that none of these mutations will be fixed?
   4. What will be average time before these mutations are fixed?
3. A genetically isolated populations was founded seven generations ago by 250 people. Number of people in subsequent generations were 300, 500, 800, 1200, 3000, 6000, 12000 and currently population comprises 20000 people.
   1. What is a chance that an allele which was present in one chromosome in founder generation is still present in current population?
   2. What is a chance that an allele which was present in 6 chromosomes in founder generation (1%) is lost?
   3. What is a chance that an allele which was present in 30 chromosomes in founder generation (5%) is lost?
   4. What initial frequency (in founders) gives an allele a high (95%) chance to stay in current population?
   5. Read breifly the paper by Pardo et al., and compare your results.
   6. Advanced question: If allele was present at frequency of 0.01 (1%) at the ORIGINAL population where the founders came from, what are the chances that it will be present at current population of the genetic isolate? Give rough estimate.