However, it’s a bit more complicated than that. In the past, research suggested that it was the dominant alleles that ruled, where hair color is concerned. People who thought their babies would have dark hair like their partner, are surprised to find they actually got their lighter locks! For hair color, the dominant alleles produce darker shades, whereas the recessive ones create lighter tones (4). These are either “dominant” or “recessive”. Your baby’s DNA comes in packages of alleles. This means that when two individuals get together, they have the potential of producing 64 trillion babies with different combinations of traits, although - thankfully - it’s not possible to have that many children (3)!īut it does mean every one of your offspring is likely to look completely different! But just to give you an idea of all the possible combinations, think about this:Įxperts believe that one human has around 100,000 genes in their 46 chromosomes. Our genes are the most dominant factor when it comes to determining how our babies will look. Or they could be a mix of you both!īut let’s go a bit deeper into the world of genes. This means that your first born might inherit your golden locks, but your second baby may appear more like your partner. All of the things that make us unique are already locked and docked this early on.Įach set of genes is individualized. Some genes determine sex, others eye and hair color, personality traits, and so on. It has 46 chromosome copies in total.Įach and every one of these chromosomes has a role.
This microscopic new cell is like computer software - it holds the genetic information from the parents. Zygote means “yoked” or “joined” in Greek, and it refers to the fertilization and formation of a new cell. Now, when the egg and sperm meet they fuse together and form what we call a zygote. That’s 23 chromosomes from you and 23 from your partner (2). You see, the sperm and egg both hold copies of the genetic makeup of each parent. This is a fact that may surprise many, but a baby’s hair color is actually determined from the moment of fertilization.
This may take some time to show, since the pigment is waiting to be activated.
If your mom or dad, or even a grandparent, had red hair, your baby could potentially turn out to be a redhead. Of course, we also have to consider our family’s history of hair color. The red hues are simply hidden beneath a light-brown tone. However, now we know that it’s possible to be a redhead. For a long time, researchers thought that red was recessive and blond was dominant. But if one of you has a little darker hair or more eumelanin, then your baby might have darker locks (1). If both you and your partner have brown hair, it’s likely your little one will have the same.
Well, we can try to predict it, but our new arrivals tend to surprise us!Īlthough there are trillions of possible combinations, the chances your baby will have something completely different are small.