Dear Participants,
Thanks for submitting your report. I will respond here and separately, via email, to Mrs. Jeffery.
When you check the other data you can confirm that white forelocks don not occur very often.
I'm interested in the observation that some students appeared to have one of each trait. The reason there is no place on the form to record this sort of situation is that such a situation has not occurred before. If attached or free earlobes are controlled by a single pair of genes, and one or the other gene is dominant, is it possible for a person to have one of each kind of earlobe? I would say no. The conclusion then must be one of these:
1. Earlobes are not controlled by a single pair of genes 2. No dominance is possible in some individuals or 3. Your observations might have been inaccurate
What do you think is the most likely situation?
I'm puzzled about the young man who is color blind. I agree that he inherited the gene for color blindness from his mother. His mother, however, couldn't have received any genes from her uncle, so I am forced to conclude that the boy's grandfather (on his mother's side) was, in fact, color blind or that the boy's maternal grandmother passed the gene for color blindess to her daughter.
As far as the dimples are concerned, I guess the real question here is how is dominance established by scientists. They observe how traits (such as dimples) are inherited in many cases. They use pedigree charts to follow the inheritance of such traits through generations. You are correct in expecting that if a trait is dominant, one or both parents must show it. I would be suspicious of results which don't appear to make sense. Have you seen the parents who are not supposed to have dimples? Do you have a picture? How can you be certain one or the other does not?
Yes, the results from one school do not provide a large enough sample to produce conclusive results.
I'm glad you enjoyed the project.
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