Some people may have red hair due to a mutation in the MC1R gene, which can result in the production of more pheomelanin (red pigment) and less eumelanin (brown/black pigment). This genetic variation can lead to the characteristic red hair color.
use simpler terms
Some people have red hair because their genes have a mistake that makes their body produce more of a red pigment called pheomelanin. This is caused by a change in a gene called MC1R, which results in the red hair color.
