The color of human hair

The document explained that human hair color was determined by the presence and ratio of two types of melanin: eumelanin and pheomelanin. The melanocortin-1-receptor (MC1R) gene played a crucial role in regulating melanin production, with mutations leading to red hair. Tyrosinase enzyme activity, which was higher in individuals with red or blond hair, controlled melanin production. Grey hair resulted from reduced tyrosinase activity due to aging. Hair color could be assessed macroscopically or microscopically, and artificial coloring could be detected microscopically. Hair was a common forensic evidence, with methods available to associate it with individuals.