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Ever wonder why some people have even skin tone, and some have freckles?

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As it turns out, science has traced it all to one gene.

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It’s called the Melanocortin 1 Receptor gene, or MC1R for short.

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When your skin is exposed to UV radiation, it responds by producing melanin, or skin pigment.

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For people who have a certain variation of MC1R, however, the melanocytes aren’t spaced evenly.

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They’re clustered, so the melanin they produce is clustered as well.

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This is also why people with freckles tend to sunburn easily…

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…and why, when freckled people get some sun, they just get more freckled, while remaining pale.

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In case you’re wondering, it is in fact the same gene that determines red hair color…

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…but it doesn’t always correlate.

What's your thoughts on this?