Inside each cell in our body, we have a blueprint that makes us who we are. This blueprint is made up of DNA, grouped in 23 pairs of chromosomes. There are thousands of genes on each chromosome. The genes are also paired. One chromosome and therefore one gene in each pair will come from your mother and one will come from your father.
One gene often dominates its paired “recessive” gene. For example, the gene for brown eyes and for blue eyes is variations of the same gene where the gene for brown eyes is dominant and the gene for blue eyes is recessive. If either one of the pair of genes, or both, are genes for brown eyes, you will have brown eyes. To have blue eyes, both genes in the pair must be “blue genes.”
The sex chromosomes are one pair of chromosomes. Women have XX sex chromosomes and men have XY chromosomes. Some genes on the X chromosome don’t have a partner. For many years, people thought that the “gene for Androgenetic Alopecia” was a recessive gene on the X chromosome and that men inherited baldness from their mother’s father. This was even written in medical textbooks but it just isn’t true.
In actuality, the genetics of Androgenetic Alopecia are much more complicated and there is still a lot of work to be done before they will be better understood. There are very likely many different genes on different chromosomes that are involved. Certainly some of the genes are dominant, since Androgenetic Alopecia is so common. Androgenetic Alopecia can therefore be inherited from either side of the family or from both sides.
To further complicate matters, there is another genetic principle called “penetrance.” The same genes may have more effect in one person than in another. One person may have light brown eyes while another person with similar genes might have dark brown eyes. You might end up with advanced balding when the only person in your family who seemed to have hair loss was your uncle who had some recession of the hairline and thinning in the crown.
To summarize, if you have Androgenetic Alopecia, like many other people, you were destined to lose hair from the time you were conceived. You have a group of genes that act together to make your hair susceptible to natural hormones in the body. You inherited these genes from either side of the family or from both sides and these genes may affect you more or less than other members of the family.BACK