No, ginger hair is not a dominant trait; it is actually recessive.
Understanding Hair Color Genetics
Hair color is determined by genes, and these genes can have different versions called alleles. Some alleles are dominant, meaning they will always express their trait if present, while others are recessive, meaning they only express their trait if two copies of the recessive allele are present.
Dominant vs. Recessive Traits
| Trait Type | How it Works | Example (Hair Color) |
|---|---|---|
| Dominant | Only one copy of the allele is needed to express the trait | Brown hair |
| Recessive | Two copies of the allele are needed to express the trait | Red/Ginger hair |
Why Ginger Hair is Recessive
The reference provided clearly states that "red hair is a recessive trait." This means that an individual needs to inherit two copies of the red hair allele (one from each parent) to express ginger hair.
Genetic Implications
- Two redheaded parents: Will almost always have redheaded children because they can only pass on the recessive red hair allele.
- One redheaded parent and one parent with brown hair: The children have a higher chance of having brown hair because the brown hair allele is often dominant. However, they can still inherit one recessive allele for ginger hair and become carriers. If both parents are carriers (one brown haired, one carrier), there is a 25% chance each child will inherit two recessive alleles for red hair.
Conclusion
Ginger hair is not a dominant trait. Its recessive nature explains why it is less common than other hair colors like brown or black. The genetic inheritance of the red hair allele is crucial for its expression.
