Advances in Quantitative genetics (Question Paper )

 

  

Answer the following:

1. Define linkage and mention the principle of detecting the same. (2.00 marks)

2. Mention the circumstances under which the parental and non-parental types of gametes are produced in equal frequency by a dihybrid. (2.00 marks)

3. At least one and/or odd number of crossovers are essential to realize recombinants. State True or False. (1.00 mark)

4. If, out of the 100 cells undergoing meiosis, 20 experience one crossover, 10 cells experience 3 crossovers, and 10 cells experience 4 crossovers, predict the number of recombinant types of gametes that could be produced by a dihybrid individual. (2.00 marks)

5. If the frequency of homozygous recessive progenies from a dihybrid is 0.4, estimate the recombination fraction, interpret, and examine the significance of the recombination fraction using the LOD score test. (2.00 marks)

6. Define mapping population and mention the types of mapping populations. Mention the most appropriate DNA marker system for genotyping different mapping populations. (10.00 marks)

7. If the frequency of recombination between two genes is 0.3, predict the frequency of crossover between them. (1.00 mark)

8. Define mapping function. Mention different mapping functions and differences between them. Mention the purpose of using a mapping function. If the recombination between two markers is 0.3, estimate the map distances using Haldane and Kosambi mapping functions. (10.00 marks)