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Pearls are precious because they take time to form inside oysters, and few of
the molluscs survive long enough to produce more than one. So biotechnologists
in Massachusetts are taking animal genes that make growth-promoting proteins and
putting them into oysters, to make them mature faster and produce pearls sooner.
The shells of the first oysters to undergo the treatment grew 2.5 times as fast
as ordinary oyster shells. They also took less time to make bigger pearls.