The suggestion comes as the DoH revealed that its upcoming autism strategy will require annual local audits of how autism diagnosis is improving.
Terry Brugha, professor of psychiatry at the University of Leicester, said GPs could develop expertise in diagnosing autism.
Assessment involves interpreting detailed questions about childhood development. He said research suggests people are not able accurately to complete self-assessment questionnaires. But expertise could be developed among GPs to complete such assessments, he argued.
'I'm very impressed with the quality of referrals we're getting from a growing number of GPs,' he said. 'They could act as a seed for primary care developing expertise in this area.'
But, he stressed, PCTs needed to develop appropriate services for GPs to refer to.
Patience Wilson, DoH deputy director for independent living, said the autism strategy would be published by 1 April.
Ms Wilson said that publication had been delayed by the high number of responses the DoH had received to its consultation on a draft of the autism strategy.
The strategy will set out how NHS bodies should increase awareness of autism among frontline professionals and develop clear, consistent path-ways for diagnosis.
The DoH wants to publish a three-year plan for the strategy, including guidance for NHS organisations, alongside the strategy itself.
The plan will include details of requirements for yearly local audits of progress against key objectives.