Oh, I suppose I should go ahead and link to that Elizabeth Taylor mutation article:
Double rows of eyelashes are usually the result of a mutation at FOXC2, a gene that influences all kinds of tissue development in embryos. FOXC2 mutations are thought to be responsible for, among other things, lymphedema-distichiasis syndrome, a hereditary disease that can cause disorders of the lymphatic system in addition to double eyelashes.
It's interesting, in its way. But I really want to pick a bone with this:
I was slightly crushed, then, to discover that, by most official accounts, Taylor's eyes were actually a deep blue that appeared purple when enhanced by lighting and makeup. (Truly violet eyes occur only in albinos.)
Blue eyes are blue because of the quality of light available for diffraction. There's no blue pigment in them, just as there is no blue pigment in the sea to make it blue. (Amusement park water is a different story...). This is why we can talk sensibly about eyes that always seem to be changing in color.
I see no reason to deny the woman her violet eyes. Heck, in my yard the violets (the sweet yard-growing kind, not the African kind) aren't even violet! Dark blue eyes with a touch of eumelanin in a shallower configuration might not match the crayon for color, but could easily be violet to anyone at Richard Burton distance.