Photos of football player Lionel Messi’s face during the World Cup in Qatar have drawn attention for highlighting a bushy red beard and very dark hair. But why does this happen? The answer is in science.
The specific gene that makes hair red is the MC1R present on chromosome 16 — a structure formed by DNA and protein molecules. Its main function is to produce a protein called melanocortin 1, capable of converting the type of melanin responsible for reddish tones (pheolmelanin) in another responsible for the black tones (eumelanin).
MC1R is recessive, so both parents need to carry the gene for a person to have red hair traits.
Thus, when a person inherits two mutated versions of the MC1R gene — that is, one from each parent — less pheomelanin is converted into eumelanin, Petra explained. haak-bloemspecialist of erfocentruma Dutch national information center on genetics and hereditary traits, told Vice magazine.
“The pheomelanin accumulates in the pigment cells and the person ends up with red hair and fair skin”, he says.
And why then can the hair be dark?
According to Haak-Bloem, hair color is genetically determined by “incomplete dominant hereditary traits”, that is, there is no dominant gene, they all influence each other.
So, when only one mutation of the MC1R gene is inherited, a red beard may (or may not) appear in a man with dark hair.
Therefore, the difference in color occurs when the same gene is behaving in different ways in different parts of the body, according to Nina Jablonski, professor of anthropology at Penn State University, in an interview with Live Science.
Jablonski also says that the red beard phenomenon can also occur in some men who are generally over 40 years old. That’s because the pigment-producing cells in the scalp and beard age at different rates.
Remembering that the reddish pigment does not necessarily appear only in the beard and in men. Red hairs can appear in other places on the body and also in women.