Question:
What is the chemical composition of Melanin by specific amino
acids, or the DNA code for melanin?
Replies:
This is a good question! The answer is somewhat complex and I'm sure
I don't have all the details but here goes... First, there is not a
specific DNA code for melanin because like many biomolecules, it
is not the result of a single gene product. People that are deficient in
melanin are oculo/dermal albinos and I believe there have been seven
different types of mutations. These different mutations reflect the
multiple steps required to produce melanin. The original building
block for melanin is tyrosine, one of the amino acids. This amino acid
is modified by enzymes to produce the building block (monomer) for
melanin synthesis by a process called polymerization that is also
controlled by an enzyme. The polymers ,I believe, can attain diff3erent
lengths and they can also form aggregates of different sizes alone
and in combination with other molecules such as proteins. This is in
part responsible for differences in coloration seen within and between
individuals. NEWTON RULES!
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