If A Jet Black Haired Parent And A Blonde Parent Have Children, What Color Hair Would The Children Likely Have?


I would like to know if there is a change that my kids will have blond or black hair. or maybe a combination …


As there are numerous possibilities in the world of genetics, everyone wants to know the outcome of what happens when two genes mix. In this case, the question is about the gene which is responsible for hair color will be dominant when jet black and blonde variants combine.

One of the most interesting aspects of genes is that everything is possible, but not all of the possibilities fall under the probable category. One explanation is that as dark genes are more dominant, when you compare them to the ones responsible for the lighter colors. Due to this reason, when one parent carries the dominant dark color gene, and the other has the recessive blonde gene, the chances of their children having dark hair is extremely high.

However, this is again with the assumption that these parents are purebred, which means that they don’t have any other types of hair color genes. As it is likely for people to carry different types of genes, the chances of having dark or blond hair drops to 50%. As genes with dark hair are more dominant, there is a very high chance that the children’s hair color will change its intensity.

One way to explain genetics is to take a look at the Law of Segregation by Gregor Mendel. While conducting a study on pea plants, he proposed that you can narrow down to a single trait and use it this phenotype to study the offsprings. As a result of this Reginald Punnet came out with a gene expression of the ratio 3:1, known as the Punnet Square. According to this ratio, three offsprings will possess the dominant trait, while the other one will have recessive genes. As proof, he used this theory on pea plants, and found that the results remained close to this number.

Another explanation is to take a look at the MC1R gene, which has a huge role as it determines the color of your eyes, hair, and skin. As this gene has numerous configurations, two people with the same hair color, may have obtained it through different methods. Also, there are other genes which can supplement MC1R, which cause different hair color. People living in Oceania have a gene mutation, which makes their hair blonde, which is not related to MC1R. At the same time, even though their hair color is similar to the Europeans, its evolution was independent.

Real life example

Taking a look at real-life situations gives you an idea of how genes work. When one parent has jet black hair, while the other is blonde, the first born had brown hair. However, once the child became a teenager, the color started becoming darker, until you could no longer distinguish it from black. The eyebrows also experienced the same phenomena, with the passage of time.

When the second child was born, the young one had blond hair. As the child entered the teenage phase, the intensity of the hue increased, until it became a dark shade of brown.


You cannot determine the exact color of the children’s hair, without having proper knowledge about the family’s genotype history.