Red hair in children is inherited through genes. Specifically, it's largely determined by variations in the MC1R gene.
Understanding the MC1R Gene
The MC1R gene plays a crucial role in pigment production. It controls the type of melanin produced—eumelanin (brown/black) or pheomelanin (red/yellow).
- Eumelanin: Produces brown and black hair colors.
- Pheomelanin: Produces red and yellow hair colors.
Inheritance of Red Hair
A child inherits two copies of the MC1R gene, one from each parent. If a child inherits two copies of a specific variant of the MC1R gene, they'll likely have red hair. This variant leads to the production of mostly pheomelanin and little eumelanin. This explains why two red-haired parents often have red-haired children. The more copies of this specific MC1R variant, the more likely the child is to have classic orange-red hair, due to a greater production of pheomelanin.
Why Some Kids Have Red Hair and Others Don't
The presence or absence of specific MC1R gene variants dictates the hair color. A child needs to inherit at least one copy of the variant from each parent to express red hair. This explains the varying shades of red across families: some are bright orange-red, others might be more auburn.
