Oliver Johnson, 16, from Whittle-le-Woods, near Chorley, was diagnosed with Leber Hereditary Optical Neuropathy (LHON) after first experiencing blurred vision on a family holiday last summer.
His sight has deteriorated to such an extent that he has had to give up playing football, although he is still able to go to school at St Michael’s, Chorley.
His parents Richard and Sheena have set up a Just Giving appeal with a target of £30,000 to fund vital treatment for the very rare genetic condition – and team-mates from his football team Brinscall Juniors joined a host of friends, family members and supports in tackling all or part of 20k runs held on both Saturday and Sunday in Astley Park, Chorley.
The marathon effort is expected to have raised several thousand pounds for the fund and Oliver’s mum Sheena said: “We can’t thank people enough. It really was a brilliant weekend and we are so grateful for everyone’s support.
Oliver’s grandma Jean Brimelow joined other family members in tackling a section of the pictures route through the Hall grounds, while his sister Francesca made cakes for the runners.
The fund has already topped £10,000, thanks to donations and fundraising efforts.
"We have been told that the eyes should stabilise in time but there is no way of knowing how much the sight will have deteriorated before that happens or when it will happen," added Sheena.
Details of the appeal for Oliver are here