'Secret' Of Youth In Red Hair Gene

They found the first part of human DNA - the genetic code - that seems to affect how old people look to others.

The mutations, reported in the journal Current Biology, were in the genetic instructions for protecting the body from UV radiation.

But these can also lead to red hair, and experts caution the findings may be confused by eye, skin or hair colour.

The study into "perceived age" was organised by the Erasmus University Medical Centre in the Netherlands and Unilever.

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