Bio D137
Human and Eukaryotic Genetics
J.L.Marsh
F'11
Prob Set 9 due
MONDAY, DEC 5 by 4pm
Name/student ID:_______________
2
2
The disease is dominant and thus, if linked to HVRA, it is linked to the 43 allele because 7/9 affected people have it while only 3
of 11 unaffecteds have it .
Female #1 is hypothesized to be M 43/+ 32 and we are testing for independent assortment so the
possible combinations in her offspring are:
Parental:
M
43
of which there are 7 i.e.
#3, 4, 8, 11, 15, 16, 22
Parental:
+
32
of which there are 8 i.e.
#5, 6, 7, 10, 12, 13, 14, 21
Recombinant:
M
32
of which there are 2 i.e.
#18, 20
Recombinant:
+
43
of which there are 3 i.e.
#9, 17, 19
Thus, the mutant is linked to the 43 allele at a distance of ~5/20 = 25 map units
One point was given for an answer of “unlinked” with a reasonable explanation.
B]
Is HVR B @ 9q22.32 linked to this disease and if so, what would you estimate the map
distance between them to be and what are the parental linkage relationships in person #1?
Please explain your work.
Answer: 2 pts
Yes (0.5pt) @ 5mu (0.5 pt) – 1 recombinant/20 total.
Parental linkage relationships =
M
23/+
20 (0.5 pt)
Show work (0.5 pt)
The disease is dominant and thus if linked to HVRB it is linked to the 23 allele because all 9 affected individuals have the marker
and only one unaffected does.
Female #1 is hypothesized to be M 23/+ 20 and we are testing for independent assortment so the
possible combinations in her offspring are:
M
23
of which there are 9
i.e.
#3,4,8,11,15,16,18,20,22
+
20
of which there are 10 i.e.
#5,7,9,10,12,13,14,17,19,21
M
20
of which there are 0 i.e.
+
23