Re: Pigmentation

Heather Rose Jones <heather.jones@xxxxxxxxxxxxx> wrote:
Tina Hall <Tina_Hall@xxxxxxxxxxx> wrote:

Always on the search for features that make humanoids different
without turning them into ugly slimey monsters, I wonder what's
behind the different pigmentation. Why do people without fur not
have various splotches? (I don't think moles/beauty spots count,
they're a different sort of skin.)

Some do -- there's an inherited human trait called piebaldism that
produces patches of unpigmented skin. Very commonly this includes a
patch along the front of the scalp that produces unpigmented hair,
usually referred to as a "white forelock".

Interesting.

As a child, I used to know (well, my grandmother did) a guy who had a
small blond patch at the back of the head (not dyed), among ordinary
brown rather curly hair. Think that's similar?

I remembered the basics of this from old genetics classes, but a web
search also seems to indicate that piebaldism is sometimes (often???)
associated with defects of the neural crest that lead to less purely
cosmetic abnormalities such as Waardenburg's Syndrome.

What's the Waardenburg's Syndrome? (I might seach for it next time I'm
online, but that may be a while.)

While it doesn't answer the more general question of why humans don't
commonly come with particolored skin, I would suspect that the
Waardenburg-related piebaldism may be self-limiting due to the more
severe effects associated with it. (But, as I note above, I haven't
found an indication of how common human piebaldism is when _not_ due
to Waardenburg's Syndrome.)

For fantasy world people, there needn't be whatever Syndromes attached.
:)

Thanks.

--
Tina
WIP: [Untitled]: 6139 words
WISuspension: Seasons & Elements trilogy | Magic Earth series
Posted to Usenet newsgroup rec.arts.sf.composition.

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