What are my chances of having a red haired child?

Editor's Note (6/10/2026): This article has been edited from its original form to improve accuracy. Wherever possible, the author’s original text was used and simply restructured to better emphasize the complexity of hair color as a trait.

Worldwide, red hair is quite rare. And a lot of people wonder about the chances that their children will be in that group!

We do know quite a lot about how red hair is inherited – but some of the details still need to be figured out!

Redhead basics

Your hair gets its color from a type of pigment, called melanin. You have two types of melanin in your hair: eumelanin and pheomelanin. 

Eumelanin is a brown pigment. It colors hair and skin shades of brown and is responsible for skin tanning. On the other hand, pheomelanin has a reddish color and is present in the lips, nipples and genitals. 

All humans have small amounts of pheomelanin in their hair. But if there’s a lot of eumelanin, the brown pigment drowns out any red color. However, if someone has very little to no eumelanin, their hair appears red. The lack of eumelanin also causes fair skin.

How does your body know how much eumelanin versus pheomelanin to make? The answers are in your genes!

As you might have heard, you inherit genetic information from each of your parents. And similarly, you pass on your genetic information to any children you may have.

Your genetic information, or DNA, is organized into small pieces called genes. Genes have the instructions to make you who you are, including your hair color! Genes come in different versions, called alleles.

While hair color may seem like a simple trait, there are actually over a hundred genes (which all have different alleles) that work together to determine your hair color! To make things even more complicated, you don’t only have ONE allele for each gene. You actually have TWO: one from each of your parents. These alleles could be identical, or they might be different from each other. 

Now, as far as hair color traits go, red hair is unique in that we actually know a decent amount about the genes and alleles responsible (at least in European populations where this hair color is more common).

MC1R: AKA “the red hair gene”

The gene that seems to play the largest role in determining whether someone has red hair is MC1R, which provides the instructions for making a protein called Melanocortin-1 Receptor. This protein plays a major role in making eumelanin, and if it doesn’t work properly, much more pheomelanin gets made instead. In fact, studies suggest that pretty much everyone with red hair that isn’t related to a genetic disorder has less-functional melanocortin-1 receptor proteins.¹

Several alleles, or versions, of the MC1R gene are responsible for these poorly functioning proteins. These different versions are caused by changes to specific letters in the DNA sequence for the gene. Geneticists refer to these differences in specific letters as single nucleotide polymorphisms, or “SNPs”. Three of the most well-studied SNPs involved in red hair include rs1805005, rs1805008, and rs1805009. While these three are some of the strongest predictors of red hair, many other SNPs in MC1R have been found that may also impact hair color.²

In most cases, it seems like you either need two matching copies of one of these alleles in order to have red hair, or you need to inherit a different red-hair associated allele from each parent. However, this isn’t always the case. 

Sometimes, someone has red hues in their hair even though they only have one copy of one of these alleles. On the flip side, someone may have two copies of alleles that are weakly associated with red hair and may not have red hair, while someone else with the same two copies of these alleles does have red hair!²

The UK biobank has data on hair color and SNPs in MC1R from thousands of individuals, and this allowed scientists to develop models for predicting whether someone will have red hair based on their DNA. Given the complexity of hair color as a trait, the best model, which had 96% accuracy in predicting whether someone had red hair, looked at 33 different SNPs in MC1R. Interestingly, MC1R sequence alone was less accurate for predicting whether someone had red versus blonde hair.²

Similarly, blonde hair is also controlled by hundreds of different versions of genes. From the UK biobank, we know that some MC1R versions are associated with blonde hair. Although MC1R isn’t the main factor in determining whether a person has blonde hair, combinations of many different gene versions, including variations in MC1R, can lead to blonde hair. And in dogs, a less-functional MC1R can produce the yellow coat that is common in golden retrievers or yellow labradors!³

The relationship between MC1R and red hair is actually quite complicated. From the same biobank study, researchers found that over 90% of redheads have two MC1R versions associated with red hair, but the reverse isn’t necessarily true: many people with two of these MC1R versions have blonde or brown hair.² So how is that possible?

The answer is: MC1R isn’t the only gene involved.

But wait, there’s more at play here!

As you might have noticed, there are different shades of red hair. It all depends on the combination of eumelanin and pheomelanin that each redheaded person has!

And what controls how much of each type of melanin your body makes? Multiple different genes are in charge of working together to give you your specific hair and skin color. 

In fact, skin and hair color depend on a bunch of different genes working together. There are dozens of genes that are known to affect hair color, and hundreds of genes for skin color. And we surely even have more to discover!

One way that genes can affect hair color is by changing the activity of the melanocortin-1 receptor, the protein that MC1R makes. To understand how, we need to learn how proteins interact with each other first.

To function, a receptor protein must bind its ligand protein. Think of it like a lock and key – the receptor is the lock, and the ligand protein is the key that ‘unlocks’ the receptor and turns it on. 

Most receptors have more than one ligand, and each ligand can serve a different purpose. Some ligands might activate the receptor to signal to other proteins, while others might stop its activity.

α-MSH and ASIP are two ligands for MC1R. They actually compete to bind the protein, and once one of them binds, the other one can’t. When α-MSH binds MC1R, it increases the amount of eumelanin that the cell makes. ASIP stops MC1R from telling the cell to make eumelanin, so it makes more pheomelanin instead.⁴

So MC1R may be the gene most strongly associated with red hair, but many other genes like ASIP are involved, too.

If that wasn’t enough, there are some external factors that can change the way genes work. 

For example, hormones can cause blonde hair to get darker as children get older. Some other factors can lead the hair color to fade, including stress, sunlight, smoking, a poor diet… 

All of that means that even if two people have the exact same combination of multiple genes … they might still have different colored hair. 

In conclusion…

Hair color genetics is surprisingly complicated! There are a lot of different genes that impact hair color, plus a lot of non-genetic factors. Scientists are still looking into the genetics of hair color, so I am sure we will have more definite answers in the near future!