Question 1

What is the Lod score?

Accepted Answer

The ratio of the two likelihoods describ...

Question 2

The mapping of the human genome in the mid-1980s was integral for identifying new human genetic markers because of the identification of what types of polymorphic DNA markers?

Accepted Answer

SNPs and r...

Question 3

Recombination analysis allows for the mapping of genes because the frequency of crossing over is proportional to what distance?

Accepted Answer

distance b...

Question 4

Which type of crossover event produces two parental and two recombinant chromosomes in gametes?

Accepted Answer

A)  single-strand crossover
B)  two-strand double crossover
C)  three-strand double crossover
D)  four-strand double crossover
E)  None of the above; all crossover events produce only recombinant chromosomes.

Question 5

How is Newton Morton's statistical method helpful for calculating the overall probability of genetic linkage when allelic phase is unknown?

Accepted Answer

Morton's method determines whether genet...

Question 6

Describe why allelic phase is a major obstacle in mapping human genes.

Accepted Answer

Allelic phase is the arrangement of diff...

Question 7

The alleles of linked genes tend to __________.

Accepted Answer

A)  segregate together during gamete production
B)  assort independently
C)  be mutated more often than unlinked genes
D)  experience a higher rate of crossing over
E)  assort independently and show a higher rate of crossing over

Question 8

In a two-point test-cross analysis, what are the "two points" being tested?

Accepted Answer

The answer of In a two-point test-cross analysis, what are...

Question 9

What is the relationship between linked genes and syntenic genes? Are syntenic genes always linked?Are linked genes always syntenic? Describe what is meant by each term.

Accepted Answer

Linked genes are always inherited togeth...

Question 10

Assuming three genes are linked, how many recombinant genotypes would you expect and at what frequency?

Accepted Answer

A)  two recombinant genotypes, more frequent than expected by independent assortment
B)  four recombinant genotypes, more frequent than expected by independent assortment
C)  six recombinant genotypes, more frequent than expected by independent assortment
D)  four recombinant genotypes, less frequent than expected by independent assortment
E)  six recombinant genotypes, less frequent than expected by independent assortment

Question 11

Which type of crossover event produces all four recombinant chromosomes?

Accepted Answer

A)  single-strand crossover
B)  two-strand double crossover
C)  three-strand double crossover
D)  four-strand double crossover
E)  None of the above; all crossover events produce a combination of parental and recombinant chromosomes.

Question 12

What is the highest possible frequency of recombination between linked genes that can be generated by any type of crossover event?

Accepted Answer

The answer of What is the highest possible frequency of...

Question 13

Incomplete genetic linkage of three genes in a trihybrid produces eight genetically different gamete genotypes. How many different gamete genotypes are produced in a four-gene cross with incomplete genetic linkage?

Accepted Answer

A)  4
B)  8
C)  16
D)  20
E)  24

Question 14

The Zmax from the analysis of a disease gene N and the DNA marker H was 2.5 at θ = 0.1. Which of the following is the best interpretation of this result?

Accepted Answer

A)  N and H are not linked.
B)  N and H are separated by 10 cM.
C)  N and H are separated by more than 10 cM.
D)  N and H are separated by less than 10 cM.
E)  No conclusion can be made regarding the linkage of N and H.

Question 15

What is the term for chromosomes that do not reshuffle the alleles of linked genes?

Accepted Answer

parental c...

Question 16

What organism exhibits complete genetic linkage, meaning there is no recombination between homologous chromosomes?

Accepted Answer

male Droso...

Question 17

Ascospores in yeast are not arranged in a particular order. Thus, the four haploid ascospores contained within a yeast ascus are known as what?

Accepted Answer

The answer of Ascospores in yeast are not arranged in...

Question 18

Genes A and B are located 10cM from each other on a chromosome. Gene C is located 25cM from gene A and 15cM from gene B. What is the probability that the trihybrid ABC/abc will produce any kind of recombinant gamete?

Accepted Answer

A)  76.5%
B)  38.25%
C)  23.5%
D)  1.5%
E)  0.75%

Question 19

For a given cross, the expected number of double recombinants is 20 and the observed number of double recombinants is 15. What is the coefficient of coincidence (c) ?

Accepted Answer

A)  0.25
B)  1.33
C)  20
D)  0.75
E)  15

Question 20

What would a Lod score of 3.2 tell you about genetic linkage? What information does the θ value tell you?

Accepted Answer

Scores of greater than 3.0 pro...

Exam 5: Genetic Linkage and Mapping in Eukaryotes

What is the Lod score?

Correct AnswerverifiedThe ratio of the two likelihoods describ...View AnswerShow Answer

What is the term for chromosomes that do not reshuffle the alleles of linked genes?

Correct Answerverifiedparental c...View AnswerShow Answer

The mapping of the human genome in the mid-1980s was integral for identifying new human genetic markers because of the identification of what types of polymorphic DNA markers?

Correct AnswerverifiedSNPs and r...View AnswerShow Answer

Describe why allelic phase is a major obstacle in mapping human genes.

Correct AnswerverifiedAllelic phase is the arrangement of diff...View AnswerShow Answer

What would a Lod score of 3.2 tell you about genetic linkage? What information does the θ value tell you?

Correct AnswerverifiedScores of greater than 3.0 pro...View AnswerShow Answer

The alleles of linked genes tend to __________.

Correct AnswerverifiedShow Answer

What is the relationship between linked genes and syntenic genes? Are syntenic genes always linked?Are linked genes always syntenic? Describe what is meant by each term.

Correct AnswerverifiedLinked genes are always inherited togeth...View AnswerShow Answer

In a two-point test-cross analysis, what are the "two points" being tested?

Correct AnswerverifiedShow Answer

Genes A and B are located 10cM from each other on a chromosome. Gene C is located 25cM from gene A and 15cM from gene B. What is the probability that the trihybrid ABC/abc will produce any kind of recombinant gamete?

Correct AnswerverifiedShow Answer

Assuming three genes are linked, how many recombinant genotypes would you expect and at what frequency?

Correct AnswerverifiedShow Answer

Incomplete genetic linkage of three genes in a trihybrid produces eight genetically different gamete genotypes. How many different gamete genotypes are produced in a four-gene cross with incomplete genetic linkage?

Correct AnswerverifiedShow Answer

What is the highest possible frequency of recombination between linked genes that can be generated by any type of crossover event?

Correct AnswerverifiedShow Answer

Ascospores in yeast are not arranged in a particular order. Thus, the four haploid ascospores contained within a yeast ascus are known as what?

Correct AnswerverifiedShow Answer

What organism exhibits complete genetic linkage, meaning there is no recombination between homologous chromosomes?

Correct Answerverifiedmale Droso...View AnswerShow Answer

Which type of crossover event produces all four recombinant chromosomes?

Correct AnswerverifiedShow Answer

Which type of crossover event produces two parental and two recombinant chromosomes in gametes?

Correct AnswerverifiedShow Answer

The Zmax from the analysis of a disease gene N and the DNA marker H was 2.5 at θ = 0.1. Which of the following is the best interpretation of this result?

Correct AnswerverifiedShow Answer

Recombination analysis allows for the mapping of genes because the frequency of crossing over is proportional to what distance?

Correct Answerverifieddistance b...View AnswerShow Answer

For a given cross, the expected number of double recombinants is 20 and the observed number of double recombinants is 15. What is the coefficient of coincidence (c) ?

Correct AnswerverifiedShow Answer

How is Newton Morton's statistical method helpful for calculating the overall probability of genetic linkage when allelic phase is unknown?

Correct AnswerverifiedMorton's method determines whether genet...View AnswerShow Answer

Correct Answer
verified
The ratio of the two likelihoods describ...
View Answer

Correct Answer
verified
parental c...
View Answer

Correct Answer
verified
SNPs and r...
View Answer

Correct Answer
verified
Allelic phase is the arrangement of diff...
View Answer

Correct Answer
verified
Scores of greater than 3.0 pro...
View Answer

Correct Answer
verified

Correct Answer
verified
Linked genes are always inherited togeth...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
male Droso...
View Answer

Correct Answer
verified

Correct Answer
verified

The Z_max from the analysis of a disease gene N and the DNA marker H was 2.5 at θ = 0.1. Which of the following is the best interpretation of this result?

Correct Answer
verified

Correct Answer
verified
distance b...
View Answer

Correct Answer
verified

Correct Answer
verified
Morton's method determines whether genet...
View Answer