The Texture And Look Of A Microscopic Object
Answer:
The unaffected mother, who is marrying in, does not carry an allele for the disease; so the affected child inherits an allele only from the affected father. No child could be affected by a single autosomal recessive allele, or X-linked recessive allele, so the trait is dominant
This is called incomplete dominance. When an something is heterozygous for an incomplete dominant gene, the resulting phenotype will be somewhere between the two. For example if a plant has a tall allele and a short one, but neither shows complete dominance over the other, the plant height will be somewhere in the middle.
