Having naturally crimson red hair is rare but possible for some people. Crimson is a rich, deep red color that stands out. Many people associate red hair with orangey and coppery tones, not the true, vivid crimson shade. So what causes natural crimson red hair and who is likely to have it? Let’s explore the genetics and other factors involved.
What Causes Natural Red Hair?
Red hair occurs naturally in 1-2% of the human population due to mutations in the MC1R gene. This gene provides instructions for making the melanocortin 1 receptor protein which is involved in pigment production.
Variants of the MC1R gene disrupt the production of eumelanin, the pigment that leads to black/brown hair colors. The reduced eumelanin allows the red/yellow pigment pheomelanin to show through more vividly, resulting in red hair.
There are multiple possible variants of the MC1R gene. Certain variants produce more dramatic, rich red hair colors.
The Genetics Behind Crimson Red Hair
To have natural crimson red hair, you need to inherit two copies of an MC1R variant associated with that hair color.
One of the key variants is called the D294H mutation. This mutation dramatically reduces eumelanin production, allowing pheomelanin to create a bold, intense red hair color.
Studies show that people with two copies of the D294H variant are more likely to have crimson red hair. About 4% of people in Ireland with natural red hair carry D294H mutations in both copies of their MC1R gene.
So while the genetics makes crimson red hair possible, it is still rare compared to other red hair shades. You have to inherit very specific MC1R mutations from both parents to achieve that vivid crimson color.
Other Genetic Factors
Besides the major influence of MC1R mutations, other genetic factors may also impact hair color, including:
– Genes affecting hair texture and structure – Crimson shows up more brightly on very straight, fine hair.
-Genes influencing pheomelanin production – Higher pheomelanin levels create more intense colors.
-Genes regulating melanocytes (pigment producing cells) – More active melanocytes can elevate pheomelanin.
These secondary genetic influences likely contribute to why some people with D294H MC1R mutations have strawberry blond or coppery hair rather than crimson red. Genetics is complex with many interacting genes.
Ethnic Background and Crimson Hair
Natural crimson red hair is most common in people of Northern or Western European descent.
Populations in these regions tend to have higher rates of MC1R mutations and additional genetics supporting rich pheomelanin production. Examples include:
| Population | MC1R Mutations | Crimson Red Hair Rate |
|---|---|---|
| Irish | 10% | 4% |
| Scottish | 13% | 6% |
| English | 6% | 3% |
This likely relates to evolutionary pressure. Pale skin absorbs more sunlight to produce vitamin D while red hair better camouflages in foggy climates.
Outside of Northern/Western Europe, natural crimson red hair is extremely rare. But someone who inherits exceptional MC1R mutations from both parents could potentially have crimson hair, regardless of ethnic background. Genetics produces exceptions.
Hair Color Changes Over Time
Many babies are born with light, reddish hair that darkens over time as eumelanin production increases. True crimson red hair often doesn’t fully develop until later in childhood around age 10.
Likewise, crimson red hair may gradually lighten to a strawberry blond or light ginger shade with age as melanin changes. The most intense crimson color is usually in the late teens to early 20s.
So while genetics gives the potential for crimson, hair color expression can vary over someone’s lifetime. The natural vivid crimson shade may only last for a number of years.
Impact of Hair Dye
Since natural crimson red hair is so rare, many people resort to hair dye to achieve that signature color.
Permanent dyes with oxidation ingredients can penetrate the hair shaft and produce very long-lasting crimson tones, especially on pre-lightened hair. Semi-permanent and temporary red dyes coat the outside of hair and tend to fade faster.
Chemical hair dyes definitely provide a way to mimic natural-looking crimson hair, though maintaining the color requires frequent touch-ups as the dye washes out. The dye results may also differ from an authentic crimson red genetic hair color.
Other Red Hair Colors
When people talk about red hair, many different shades come to mind. Natural red hair can range from deep burgundy to strawberry blond. Here’s a look at some other common red hair colors and how they compare to crimson:
| Red Hair Color | Color Description | Associated Genetics |
|---|---|---|
| Auburn | Rich, reddish brown | Mix of eumelanin and high pheomelanin |
| Ginger | Golden reddish orange | Moderate pheomelanin with some eumelanin |
| Strawberry Blond | Light peachy reddish blonde | More eumelanin with lower pheomelanin |
| Crimson Red | Vivid, deep, blue-based red | Very low eumelanin, two D294H MC1R mutations |
So while strawberry blond hair is also quite rare, it is more genetically common than having two copies of a rare allele like D294H needed for crimson. All red hair shades require MC1R mutations reducing eumelanin, but crimson needs very specific genetics.
Conclusion
Natural crimson red hair is possible but requires a rare combination of genetic factors. Key requirements are inheriting two copies of an MC1R mutation like D294H, minimal eumelanin production, and exceptional pheomelanin levels.
This genetic combination is most prevalent in those with Northern or Western European ancestry, particularly Celtic groups though still uncommon. While many seek crimson hair through dye, the truly natural vibrant crimson shade is exceptionally unique and beautiful.