What genotype represents woolly hair in the given scenario?
The genotype that represents woolly hair in this scenario is WW.
Understanding Woolly Hair Inheritance
In Norway, some families carry an inherited trait known as "woolly hair", which is characterized by hair that resembles sheep's wool. This trait is passed down from generation to generation through family pedigrees. The study of these pedigrees reveals that a child will only have woolly hair if at least one parent also has this trait.
The allele for woolly hair is a dominant allele, denoted by the symbol "W". This means that an individual only needs to inherit one copy of the dominant allele to express the woolly hair phenotype. In the scenario provided, the father in the family has woolly hair, indicating that he carries at least one copy of the dominant allele.
However, the father's wife does not have woolly hair, implying that she does not possess the dominant allele. In genetic terms, she would have the genotype ww, with both alleles being recessive.
When parents have genotypes Ww (father) and ww (mother), their children can inherit different combinations of alleles. The child without woolly hair in this case has the genotype ww, inheriting two recessive alleles from both parents.
On the other hand, the child with woolly hair must have inherited the dominant allele (W) from the father. Therefore, the child's genotype would be WW, resulting in the expression of the woolly hair phenotype.
This example illustrates how the inheritance of traits, such as woolly hair, follows genetic principles governed by dominant and recessive alleles. The study of family pedigrees can help trace the transmission of these traits across generations.