What will be the frequency of AaBB genotype in a dihybrid cross?

In a dihybrid cross, both parents have the genotype AaBb. To find the frequency of the AaBB genotype, we need to calculate the probability for each gene separately and then multiply them.

For gene A (Aa × Aa):


The possible genotypes are AA, Aa and aa with probabilities 1/4, 1/2 and 1/4 respectively.

So, the probability of getting Aa is 1/2.

For gene B (Bb × Bb):



The possible genotypes are BB, Bb and bb with probabilities 1/4, 1/2 and 1/4 respectively.

So, the probability of getting BB is 1/4.

Now, multiply the two probabilities to get the frequency of AaBB:

Frequency of AaBB = (1/2) × (1/4) = 1/8 = 0.125

Therefore, the frequency of AaBB genotype among the offspring is 1/8 or 0.125.





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