• Question: why do some people have two different coloured eyes?

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      Asked by to Kate, Kieren, Rowena, Roy on 19 Mar 2014. This question was also asked by .
      • Photo: Rowena Fletcher-Wood

        Rowena Fletcher-Wood answered on 19 Mar 2014:


        This is probably due to a split between halves of the brain, so one gene can be expressed on one side and one on the other. My husband has eyes which don’t “talk” to each other, so they look in different directions.

        Different coloured eyes can also be the result of some kind of pigment growth or bacterial infection (but in this case you are not born with it). Such an infection can be completely safe and only manifest itself in changing the colour of one eye. I have seen cats with different coloured eyes but not people – my old cat Rupert had two green eyes and started getting freckles in one eye when he was about 1 year old. By the time he died at 15 that eye was entirely brown.

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