Lance O'Sullivan reveals family health crisis

Seven weeks ago, Dr O'Sullivan found out his youngest son Lance Junior had Duchenne Muscular Dystrophy, Radio New Zealand reported. Photo / Facebook

New Zealander of the Year Dr Lance O'Sullivan has revealed a personal health crisis today - his 6-year-old son is suffering from a rare and life-threatening condition.

Seven weeks ago, Dr O'Sullivan - who has dedicated his life to helping his Northland community - found out his youngest son Lance Junior had Duchenne Muscular Dystrophy, Radio New Zealand reported.

Dr O'Sullivan spoke out about the family's personal health crisis on World Duchenne Muscular Dystrophy Day.

He said, as a doctor, he knew what the condition would mean for his son.

It was likely he would be wheelchair-bound by 12, lose the use of his arms by about 18 and have breathing difficulties and heart disease issues by 20.

Dr O'Sullivan said he and his wife called a whanau meeting to explain the condition to their other six children once they heard the diagnosis from a specialist, Radio NZ reported.

He said Lance Junior was not able to walk as far as other children when he was a youngster, falling over a lot and struggling to keep up on the rugby field.

Duchenne muscular dystrophy is a genetic condition that involves muscle weakness and worsens quickly.

It affects 1 in 3500 births in the world, largely boys, and leads to progressively worsening disability.

Death usually occurs by 25 typically from lung disorders, the US Library of Medicine states.