Path: utzoo!attcan!ncrcan!ziebmef!hjsdvm
From: hjsdvm@ziebmef.uucp (Howard J. Scrimgeour)
Newsgroups: sci.bio
Subject: Re: Albino Fish (was Re: The birds and the beaks)
Message-ID: <1989Apr27.124419.24994@ziebmef.uucp>
Date: 27 Apr 89 16:44:17 GMT
References: <273@acates.UUCP> <1947@ditsyda.oz> <1490@percival.UUCP>
Reply-To: hjsdvm@ziebmef.UUCP (Howard J. Scrimgeour)
Organization: Ziebmef Public Access Unix, Toronto, Ontario
Lines: 26

In article <1490@percival.UUCP> gary@percival.UUCP (Gary Wells) writes:
>It could also be that the coloring agents in the skin need exposure to UV (or
>some other component) to "darken".  I think that myolin is the pigment agent
>in human skin, and that is definitely sensitive to UV (thus sun tans).  I may be
>wrong on the name of that pigmenting agent, but the fact remains.
>
>Has anyone tried exposing any of the cave-albinos to normal levels of UV and
>checking what happens to the skin color?
>
>Just thinking out loud, here.
>


A couple of minor quibbles here. First, the pigment you're thinking of
is melanin, which is produced by specialized cells in the skin,
called melanocytes. Albinos have a genetic defect which blocks the
ability to manufacture the pigment.

The phenomenon of suntanning is not caused by U-V making the pigment
change colour. Rather, exposure to U-V stimulates the melanocytes to
produce more of the pigment.

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H. J. Scrimgeour, D.V.M.
hjsdvm@ziebmef.uucp
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