× Didn't find what you were looking for? Ask a question
Top Posters
Since Sunday
a
5
k
5
c
5
B
5
l
5
C
4
s
4
a
4
t
4
i
4
r
4
r
4
New Topic  
jessica90 jessica90
wrote...
Posts: 11
Rep: 0 0
10 years ago
This question involves Drosophila. Order and give the map distance for these three loci involved in this question:

wingless (w)   legless (l)   buggy (b)

The phenotypes indicated above are recessive.

A cross between a wild-type female and a male that expresses all of the above recessive phenotypes gives the following progeny:

1.    805  wingless legless buggy-
2.    813  wild type-
3.    112  wingless-
4.    114  legless buggy-
5.    125  wingless buggy-
6.    122  legless-
7.    3  wingless legless-
8.    3  buggy-


(a)    What is the order of the genes on the chromosome


(b)    Calculate the recombination frequencies of each region. Then draw a chromosome map of the alleles, giving distances between each allele (use the first letter of each word as the allele designation). What is the total distance?

(c)    Identify which classes are parental (p), single crossover in region 1 (sco1), single crossover in region 2 (sco2), and double-crossovers (dco).


(d)    Is there interference here? Calculate the coefficient of coincidence and give the interference.
Read 1044 times
2 Replies

Related Topics

Replies
wrote...
10 years ago
a) The order of the genes on the chromosome is wingless-buggy-legless (wbl)

b) Recombination frequency in region 1 and region 2 are 11% and 12% respectively.

    w----11%---b----12%----l
    ---------23%----------------

c) Parental genotypes are wlb and +++
    Genotypes of single crossover in region 1 are w++ and +bl
    Genotypes of single crossover in region 2 are wb+ and ++l
    Genotypes of double crossover are w+l and +b+

d Coefficient of coincidence is 0.45. Interference= 1-0.45. I=0.55
wrote...
10 years ago
great. thanks for your help
New Topic      
Explore
Post your homework questions and get free online help from our incredible volunteers
  1175 People Browsing
 109 Signed Up Today
Related Images
  
 86
  
 303
  
 329