• Question: My brother, granddad, and my granddads granddad all had ginger hair. Why does it always skip a generation?

    Asked by anon-181891 on 15 Jun 2018.
    • Photo: Donna MacCallum

      Donna MacCallum answered on 15 Jun 2018:

      Ginger hair is encoded by a recessive gene, so parents need to have a copy of the gene which need to be inherited by their child. Your dad or mum was carrying a copy of the gene, and your other parent also had one and your brother got both… do you have ginger hair? if not, you may be carrying the ginger gene and might pass it on to your children.

      My daughter would ask if you are Weasleys? She would love to have ginger hair!

    • Photo: Claire Donald

      Claire Donald answered on 17 Jun 2018:

      As Donna says its all to do with genetics. Your DNA is made up of different genes which determine things like hair and eye colour. Genes come in different forms called alleles which can be either dominant or recessive. Dominant genes always show up, even if the person only has 1 copy. A recessive allele only shows up if the person gets 2 copies (1 from their mum and 1 from their dad).

      So for a child to get ginger hair from their parents, both parents must have 1 copy of the recessive ginger hair allele. This means they are classed as carriers for that gene. It doesn’t show up in parents as they have a dominant allele for another colour (like brown or blonde). But if both parents pass on the recessive ginger allele to their child then they will have 2 copies and the ginger hair colour will show up. There is a 1 in 4 chance this will happen. There is also a 1 in 4 chance the child will get the 2 dominant alleles and a 2 in 4 chance they will become carriers themselves.

Comments