A terminally ill baby boy whose mother claimed doctors refused to keep him alive died of natural causes, a coroner ruled today.

Luke Winston-Jones, who had the rare genetic disorder Edward's syndrome, died aged 10 months at Liverpool's Alder Hey hospital last November after the high court ordered that life-saving treatment be withheld.

His mother Ruth claimed that doctors did not do their best to save Luke's life as they refused to administer adrenaline and "dismantled" breathing aid apparatus before he died.

Edward's syndrome affects one in 5,000 infants and is characterised by congenital heart disease and problems with the lungs and digestive system. The majority of babies with the condition die within their first year of life.

Liverpool coroner Andre Rebello concluded that Luke died of cardiac failure caused by Edward's syndrome.

Mr Rebello said: "Luke was born with an extra chromosome 18 in all his cells. This natural disease process ran its full course resulting in his death on November 12."

Doctors caring for Luke were granted permission by the high court last October to withhold lifesaving treatment if his condition deteriorated. Mrs Winston-Jones fought the application by Royal Liverpool children's NHS trust and North West Wales NHS trust.

But Dame Elizabeth Butler-Sloss, president of the high court family division, ruled in favour of the doctors.

She said Luke should not be resuscitated by mechanical ventilation if his condition worsened, but could be given the less aggressive treatment of cardiac massage.

The case went to the high court only two weeks after a judge ruled that another seriously ill baby, Charlotte Wyatt, from Portsmouth, should not be given aggressive treatment and should be allowed to die peacefully.