Blood Type Genotype # of individuals Frequency of Genotype M MM 360 0.36 MN MN 4
ID: 79067 • Letter: B
Question
Blood Type
Genotype
# of individuals
Frequency of Genotype
M
MM
360
0.36
MN
MN
480
0.48
N
NN
160
0.16
A population sample of 1,000 individuals was made for the MN blood group. The genotypes are easily measured since the alleles are co-dominant individuals were blood typed and the results are shown in the figure. Assume the population is in equilibrium. The frequency of M allele in the population is ? _______________. The frequency of the N allele in the population is ? ________________ Now suppose that the population is mating randomly : The frequency of the MM x MM mating is ?______________ The frequency of the MM x MN mating is ? _____________The frequency of MM x NN mating is ? _______________ The frequency of the MN x MN mating is?___________ The frequency of the MN x NN mating is ? ______________The frequency of the NN x NN mating is ?_____________
Blood Type
Genotype
# of individuals
Frequency of Genotype
M
MM
360
0.36
MN
MN
480
0.48
N
NN
160
0.16
Explanation / Answer
1. To calculate allelic frequency we use following formula.
Allelic frequency= [2x Homozygous population of the allele + Heterozygous population]/ [2 x Population]
For M = [2 x 360 + 480] / 2 x1000 =[720+480] /2000= 1200/2000 =0.6
For N according to Hardy Weinberg equation p+q =1
N =1-0.6 =0.4
2. Frequency of MM x MM mating = multiply each allelic frequency =0.6 x 0.6 x 0.6 x 0.6 = 0.1296
3. Frequency of MM x MN mating= 0.6 x 0.6 x 0.6 x 0.4 =0.0864
4. Frequency of MM x NN mating = 0.6 x 0.6 x 0.4 x 0.4 = 0.0576
5. Frequency of NN x NN mating =0.4 x 0.4 x0.4 x 0.4 =0.0256