Cassie Graves
London-based singer Cassie Graves opens up about rare condition Trimethylaminuria Facebook

An up-and-coming British singer has opened up about a rare condition which causes her to smell of rotting fish.

Cassie Graves, 22, has suffered from the uncommon genetic disorder trimethylaminuria (TMAU) since the age of three.

"You know when you go to the food market and there's rotting fish? That's what I smell like," she explained.

"The whiff comes out from my skin and hair. I sweat it out and it doesn't matter how many showers I take, I just can't get rid of it," she added, as quoted by the Metro.

"There were times when I smelt so badly of fish that my mum wouldn't let me go to school because she didn't want me to be bullied by the other kids. And it's hardly ideal to have to go on stage and give a performance when you stink of fish!"

Graves's condition means her body is unable to break down trimethylamine, a malodorous chemical that is produced in the gut, particularly when certain protein and choline-rich foods, notably fish, are digested.

Normally, the body naturally breaks down trimethylamine into an odourless molecule thanks to an enzyme called FMO3. However the enzyme is either missing, or defective, in those with trimethylaminuria.

Symptoms of the condition include a strong odour in sweat, urine and breath. Graves is unable to detect her own odour and has to rely on friends and family to tell her.

"The fact that I can't sniff it out myself is the most frustrating thing about the disorder. It makes you paranoid," she said.

"Over the years, I've tried to re-introduce small amounts of fish into my diet again to see if I had grown out of it. But each time, I wake up the next morning and my whole bedroom reeks of fish."

She added that her boyfriend Dom Oliver, a 21-year-old student, is supportive of her condition, which causes her to carefully watch which foods she eats.

"He helps me with my restricted diet. We also have a pact that if I stink of fish in the morning, he'll tell me immediately and try not to laugh."

It is estimated than 1% of the UK population are carriers of the faulty gene that causes trimethylaminuria. Women are more likely than men to have the condition, as it is believed female sex hormones such as progesterone and oestrogen aggravate the symptoms.