I just realized that there's a problem with the way I presented the data for the first mother in the problem set. This is what's in the problem set as posted:
Here's the problem. A0 is a null allele. That means that when we score the offspring we can't tell an A0A123 offspring from one that's A123A123, just as we can't tell whether a human being with blood type A is homozygous for the a allele or heterozygous for a and o. So this line of the table should really read
In other words the A123 phenotype among offspring of this mother includes two genotypes, A123A123 and A123A0.
| Maternal Genotype | Seed genotype | ||||
| A0A123 | A0A0 | A0Ax | A0A123 | A123Ax | A123A123 |
| 1 | 10 | 0 | 10 | 3 | |
Here's the problem. A0 is a null allele. That means that when we score the offspring we can't tell an A0A123 offspring from one that's A123A123, just as we can't tell whether a human being with blood type A is homozygous for the a allele or heterozygous for a and o. So this line of the table should really read
| Maternal Genotype | Seed phenotype | |||
| A0A123 | A0 | A0Ax | A123Ax | A123 |
| 1 | 10 | 10 | 3 | |
In other words the A123 phenotype among offspring of this mother includes two genotypes, A123A123 and A123A0.
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