The brothers of a talented athlete who died of sudden heart failure have urged young people to get themselves screened for the hidden genetic condition which killed him.

Dominic Hamlyn, 24, suffered a cardiac arrest at his brother Benedict's 21st birthday party last July and died 15 hours later in hospital.

The student became unresponsive during an underwater swimming competition in the pool at his family’s home near Canterbury.

An inquest in January found that Dominic died as a result of the rare genetic condition Sudden Arrhythmic Death Syndrome (SADS), sometimes known as Sudden Athlete Death Syndrome.

Now Benedict and his brother Gabriel are spearheading a social media drive to alert young people and their families to the potential threat of the condition.

The siblings have won the backing of a number of celebrities - including Fraser T Smith, the producer of hit records by Stormzy and Adele; actress Kathy Burke; Formula One commentator Martin Brundle; and Strictly Come Dancing presenter Claudia Winkleman - for their campaign to raise awareness about the devastating condition, which kills an estimated 12 young people every week.

They say families of any known victims of SADS should be screened immediately, as the condition can be inherited, along with the families of young people who have died from drowning, a fall or vehicle crash for no obvious reason - as these could mask SADS as having triggered the death.

Launching their campaign Gabriel Hamlyn said: “The pain and torment of the last 6 months have been immense. I am at the beginning of a long and lonely road without him. In losing Dominic, the world has lost one of its brightest lights. However, the painful reality is that opportunities to prevent the young deaths are often missed. Dominic will never return, but with your help, we can prevent more young candles being blown out before their wick is at its end. In life Dominic gave so much to others, his death must not come in vain.”

In a joint appeal Gabriel and Benedict said: “Many victims have warning symptoms, which if diagnosed are readily treatable, if missed or brushed aside the consequences are deadly. Any young fit person experiencing frequent dizziness, blackout or faints should get screened by heart specialists immediately.

“The lack of awareness among young athletes and the wider medical profession surrounding SAD is killing young people in Britain and around the world every day. Yet it is easily preventable by the simple screening of victims’ families and the early investigation of warning symptoms in young people.”

They added: “In the meantime, we as brothers have one message, one wish, one duty, which is to ensure that other little brothers and sisters get to watch their ‘Dominic’ grow up, marry, smile, laugh, hold their newborn children, and experience the joys of life like he never will.”