CMN: 'For someone to see the way I look as art is amazing'
Gemma Whyatt has birthmarks covering her upper back, neck, chest and ear, with hundreds of smaller marks all over her body.
It's a rare skin condition called congenital melanocytic naevus (CMN).
The 24-year-old from Cambridgeshire is one of 30 people with CMN taking part in an international exhibition.
"For someone else to see the way I look as art and something to be celebrated is really amazing for me," she tells Radio 1 Newsbeat.
Gemma, a fourth-year medical student in Leeds, was born with CMN, which is untreatable: "I was told they were my brown patches or birthmarks."
As a child she says her life was like anyone else's.
"I did normal things and had normal friends and I even did gymnastics and trampolining - which involved a leotard that revealed my birthmarks and I didn't think anything of it when I was growing up.
"It wasn't until I became a teenager that it really affected me.
"I realised I looked different and I felt quite self-conscious about it - I didn't really know anyone else with the condition.
"I used to wear scarves, long sleeves, and I would wear full aussie cozzies instead of bikinis."
But Gemma tells us she just got "fed up" of feeling self-conscious and when she was around 17 she booked a holiday to Spain with her friend where, for the first time in years, she wore a bikini.
"No-one even stared or said anything. It was kind of like exposure therapy in a way.
"I started enjoying life more to the full. It made me realise it's not that big a deal and I didn't need to limit myself."
Gemma was the first person to sit for the photographer behind the How Do You C Me Now? exhibition and tells us it was "scary and nerve-racking".
"I was only wearing my pants, with someone I've never met. I wasn't wearing any make-up and I didn't do anything with my hair.
"Usually I like to be in control of how I look and how I'm perceived, especially when taking pictures. But to give all of that to someone else did make me feel quite vulnerable.
"In doing so, it made me come to terms more with how I look and that I can't always have control over how other people see me."
Photographer Brock Elbank says: "It's about celebrating unique individuals and to have hair and make up detracts away from their natural beauty."
CMN charity Caring Matters Now worked with Brock to find those who were willing to take part.
It took three years to complete and features children and adults from 13 countries.
Gemma says people from around the world have already contacted her.
"It's not only about how it's making me feel - people have got in touch and it's given them their confidence. Or parents of young children that hope it'll make their child feel better about themselves.
"I just really hope that when people look at these images they can feel challenged in the way they perceive beauty and see the beauty inside and outside.
"It's not beauty despite the birthmarks, it can be beauty because of the birthmarks.
"It's something interesting and different and unique and I really hope it might change the way they might think of people with visible differences."
The exhibition is running from 14-24 March at the Oxo Tower gallery in London before going on a global tour.