A widow’s peak is a V-shaped point at the center of the hairline on the forehead. It is determined by genetics and is often used as a classic example in discussions about dominant and recessive traits.
The trait for a widow’s peak is generally considered to be dominant, represented by the allele ‘W’. The trait for a straight hairline, which is the absence of a widow’s peak, is recessive and represented by the allele ‘w’. Thus, the possible genotypes for someone with a widow’s peak can be either:
- Homozygous Dominant (WW): This individual has two copies of the dominant allele, resulting in a strong expression of the widow’s peak.
- Heterozygous (Ww): This individual has one dominant allele and one recessive allele. They will also express the widow’s peak phenotype due to the presence of the dominant allele.
On the other hand, someone with a straight hairline would have the genotype homozygous recessive (ww), indicating they do not have the widow’s peak trait at all. In summary, the possible genotypes for an individual with a widow’s peak are either WW or Ww.