BIG INTERVIEW: A personal view of autism - Mark Hutchings, youth andchildren's worker, Bethnal Green Mission Church

So his father, Mark, understands better than most the effects of autism, a lifelong developmental disability that is characterised by impaired social relationships and communication and by a lack of imagination. But there are few who have the opportunity or the drive to use this knowledge in their professional life.

Hutchings works with socially excluded young people in Bethnal Green, a deprived area of east London. Some of these young people have autistic tendencies, so it is both for personal and professional reasons that Hutchings is to put his 41-year-old body through the brutal trial of the London Marathon.

He is pounding the streets in preparation for the 26.2 mile race on 18 April, as a member of a 120-strong team in aid of the National Autistic Society.