Madeleine McCann: Rare condition coloboma made her easily recognisable

TW: Mentions of abduction

Madeleine McCann went missing in 2007 while on holiday with her family. Her disappearance shocked the world, and her case went on to be highly publicised. Her parents, Kate and Gerry, were considered suspects for a long time, and the Portuguese police recently apologised to them for the way they treated the case. Now, the prime suspect for Madeleine's abduction is Christian Brueckner, who is set to go to trial on February 16.

One of the key issues in Madeleine’s case, as it has lasted so long, is the problem of identification. She was three when she was taken from the holiday resort room she was sharing with her twin siblings. She would now be 20. Though many believe that she was killed, Madeleine did have a very rare condition that could have helped to identify her. You may have noticed in photos that her pupil seemed to extend into her iris: this is called coloboma.

What is coloboma?

Coloboma is a rare condition that people are born with when the eye doesn't form fully during pregnancy. It means that part of the tissue that makes up the eye is missing, and it can affect one or both eyes. According to the National Eye Institute, coloboma can also impact more than one part of the eye: as well as the iris, it can affect the uvea, lens, retina, macula or even the optic nerve. The most common form can be seen in the iris, and it often makes the person’s pupil take a more key-hole shape rather than a perfect circle.

Coloma is very rare as only one baby in every 10,000 births has the condition. Maddie’s type - of the iris - could affect as few as seven out of one million people. Retired detective chief inspector Mick Neville previously told The Sun: 'If an image search was carried out for females in an age range of three to 15 with this eye marking then you may only have a few hundred in the UK and tens of thousands worldwide. It would be an easily manageable number to scan through.'

Does coloboma impact vision?

This rare condition is always visible, so it can be identified at birth, but it is not curable. It is hard to tell whether coloboma will impact a child’s vision until they are older, but those with the condition are urged to have six-monthly and then yearly check-ins.

Some children with the condition will have to wear glasses, and as adults people can decide to get surgery or use cosmetic contact lenses to make the pupil appear round. Those with coloboma may also experience a sensitivity to light.

If you hadn’t noticed Madeleine’s eyes before, take a closer look the next time you see a picture of her - she clearly has a keyhole-shaped pupil that makes her stand out.

Read more:

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Sources used:

The Sun: THE MARK OF MADDIE What is coloboma? Madeleine McCann’s eye defect explained

National Eye Institute: At a glance: Coloboma