Question

For the MN-blood group system, the frequencies of M and N alleles are 0.7 and 0.3, respectively. The expected frequency of MN-blood group bearing organisms is likely to be a. 42% b. 49% c. 9% d. 58%

solve this question..

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Answer 1

we know that

given

p = 0.7

q=0.3

we know that

(p + q ) = p^2 + q^2 + 2pq=1

since

MN = 2pq

MN = 2*0.7*0.3

now percentage = MN*100/1

=2* 0.3*0.7*100= 42%

Answer 2

Answer:

Hardy-Weinberg principle stated that in a given population the frequency of occurrence of alleles of a gene is supposed to remain fixed and even remain the same through generations. He represented it using algebraic equation (p+q)2 = p2 + 2pq + q2 = 1, where p and q are individual frequencies of two different types of alleles.

So the expected frequency can be calculated using this equation.

For MN-blood group system:

Let frequencies of M be p, and from question p = 0.7

Let frequencies of N be q, and from question p = 0.3

Substituting these values in the above equation, we get

(p + q)2 = p2 + 2pq + q2 = 1

(p + q)2 = (0.7)2 + 2(0.7)(0.3) + (0.3)2 = 1

(p + q)2 = 0.49+0.42+0.09 = 1

So from the above equation we can see that frequency of MN-blood group organism is 2pq = 0.42, or 42%.

So, the expected frequency of MN-blood group bearing organisms is likely to be 42%.

Hence the correct answer is option (a).