How do you tell if a mutation is on the X chromosome?

Answer 1

Keep in mind that females are XX, while males are XY. What this means is that females can be carriers for the mutation since they have two X chromosomes, while males will express the mutation, since they only have one X chromosome to express. When looking at a pedigree chart, start looking at the mutation possibly being X-linked if it skips generations (since moms can be carriers that don't express the phenotype) and is especially prominent in males (since males only have to inherit one copy, while females must inherit two)!