Please Explain How Balding Skips a Generation

What exactly is meant by the phrase “balding/hair loss sometimes skips a generation”? I know it’s very complicated to say if this is true or not, but I was wondering what exactly it means. For example, if a family has 2 sons, one age 26 and one age 20, does it mean only 1 of them may keep their hair if balding skips a generation, or both? I hope you can clarify this a little bit as I am very curious as to what is meant. Thank you.

Not everyone in a balding family has the balding genes. Genes have “expression” which means that the way it shows up (for genetic balding) appears at different points in the life of the person carrying the gene. You might have the gene, but not show the balding until you are 25, 30, 35 or 40 and so on.

You may also have the gene and not express it at all. Or you may have the gene, but it is not dominant in you, so you will not show balding… but can pass it to your children who can then show balding. Without getting too deep into evolutionary biology, I hope this short answer does not confuse you further.

If you really want more details, research the work of David Balding, a UK-based professor that has written multiple publications about statistical genetics.