Blaschko’s lines happen mostly in mosaicism, where an embryo is formed by the fusion of two embryos, gets a mutation early in development, or otherwise gets two different genotypes. It can also be caused by X-linked genes. If those genotypes produce different skin colours or react differently to skin diseases, you can see the lines directly.
It looks like any visible form of mosaic disease may present along Blaschko’s lines.
Blaschko’s lines happen mostly in mosaicism, where an embryo is formed by the fusion of two embryos, gets a mutation early in development, or otherwise gets two different genotypes. It can also be caused by X-linked genes. If those genotypes produce different skin colours or react differently to skin diseases, you can see the lines directly.
It looks like any visible form of mosaic disease may present along Blaschko’s lines.