Can you help me answer a and b? Thanks Consider two parents. One parent has 5 re
ID: 87860 • Letter: C
Question
Can you help me answer a and b? Thanks
Consider two parents. One parent has 5 repeats at the TH01 locus on both of her homologous chromosomes. The other parent has 10 repeats on both of his. a. If you were provided with DNA from each of these individuals, and performed a PCR with primers specific to each end of the TH01 region, how long would the fragment you generated be for each of the parents? (Ignore the length of the primer in your calculations!) b. If you were provided with DNA from a child of their, what would you expect the result of your PCR analysis to look like? (That is, what size fragments would you generate?) Explain how you are able to make this prediction! c. Now consider a crime scene in which two offspring from these same parents (siblings!) are both suspects. Could a DNA profile based on just this TH01 region determine which sibling had committed the crime? Why or why not? If not, how might you improve your profiling to be able to distinguish these two individuals?Explanation / Answer
Answer a) It is said that each PCR cycles doubles the size of the DNA. Denotated as 2cycles . Let us assume that the above mentioned DNA undergoes 5 cycles. thus number of copies of the DNA is increased to 25 = 10. Each DNA from father has 5 repeats of TH01. Thus 10 copies will have 50 repeats.
Likewise for mother's DNA. 10 copies. each copy has 10 repeats thus total of 100 repeats.
Answer b) Based on the dominance of the gene. let us consider that TH01 with 5 repeats is dominant while TH01 with 10 repeats is recessive. Based on the law of inheritence the chances of TH01 with 5 repeats than 10 repeats in the child will be 3:1. So let us assume that child has 5 repeats of TH01. thus when it undegoes 5 cycles of PCR. the length of DNA will contain 50 repeats of TH01.