The 24 December 2006 issue of the Philadelphia Inquirer has an article which says the following
Does the above describe the normal inheritance for male pattern baldness? It seems consistent with the rarity of female baldness compared to the frequency of male baldness.
Is there some other type of inheritable baldness which does not follow the above rules?
BTW: It is my understanding that hemophilia, left handedness, and some types of color blindness also follow the above rules.
- Baldness can be inherited from either the mother's or the father's side of the family or from both sides. It may or may not skip a generation.
- Women have a pair of X-Chromosomes, while men have an X & a Y.
- Daughters get one X-Chromosome from the father & one from the mother. In order for the daughter to inherit baldness, she must have the gene on both X-Chromosomes.
- If a bald father contributes a Y-Chromosome, the result is a boy, making it impossible for a son to inherit baldness from a bald father. The son could get an X-Chromosome with the gene from his mother causing him to become bald.
- If the bald father contributes his X-Chromosome, the result is a girl. The girl will become bald if the X-Chromosome from her mother also carries the gene. Grandsons of the bald man via his bald daughter will inherit the gene and become bald (The gene could come from either side of the family). Granddaughters will be carriers of the recessive gene, but will only be bald if their father is bald.
- If the bald father contributes his X-Chromosome and the mother contributes an X-Chromosome without the gene, the girl will not become bald (gene is recessive), but has a 50-50 chance of passing the gene to a son, making him bald.
- A woman requires a bald father and a bald grandfather to have a 50-50 change of becoming bald.
- A man requires only a bald grandfather to have a 50-50 chance of becoming bald (assuming that his mother is not bald).
Does the above describe the normal inheritance for male pattern baldness? It seems consistent with the rarity of female baldness compared to the frequency of male baldness.
Is there some other type of inheritable baldness which does not follow the above rules?
BTW: It is my understanding that hemophilia, left handedness, and some types of color blindness also follow the above rules.