The report has identified some successes in research into autism, but there is still a long way to go to better understand these disorders

Professor Eve Johnston, review chair

"Our findings are consistent with the previous MRC reviews and with the findings of other expert groups that have reviewed this question."

In its assessment of the distribution and causes of autism, it found the disorder affects approximately six in 1,000 children under eight years old.

The review was commissioned by the Department of Health last March, with the aim of helping to meet the longer term needs of people with autism and their families.

The panel consisted of a number of experts, with input from lay people, including representatives from autism campaign groups.

Scientific approach

Professor Eve Johnston, who chaired the review, said: "The report has identified some successes in research into autism, but there is still a long way to go to better understand these disorders."

MRC chief executive Professor Sir George Radda, said: "Our report has identified current gaps in knowledge about autism and we hope our findings will stimulate the research community to develop proposals that address the key issues.

"We want to encourage scientific proposals for multi-disciplinary research around shared research strategies.

"We believe collaborations will lay the basis for more effective approaches to diagnosis, treatment and perhaps, in the long term, to ameliorate the more disabling effects of autism spectrum disorders, identify 'at risk' groups and target interventions accordingly."

But one organisation is not happy with the findings.

Flawed research

Justice, Awareness and Basic Support (Jabs), the support group for vaccine damaged children, believes the review is flawed.

Jabs co-ordinator Jackie Fletcher said: "They need to look at the right children in their research.

"We have a huge body of children here in the UK with autism, who have had the MMR vaccine, and we want to find out what's coincidence and what's a problem.

"They're trying to sweep these children away without trying to find out why."

The review says theories that environmental factors like diet, drugs, toxins and infections may affect autism, require further high-quality research to be scientifically substantiated.

Dr Mansfield: offered single vaccines

The report recommends further research needs to be carried out, especially using large population studies.

Last month, a doctor reported to the General Medical Council (GMC) after offering an alternative to the controversial MMR jab was formally cleared.

Dr Peter Mansfield, who has a private practice in Louth, Lincolnshire, defied the government and allowed parents to opt for the single measles vaccine instead of the combined MMR type.

Worcestershire Health Authority reported him to the GMC, saying that by offering the single jab, he was not acting in the best interests of his patients.

But the GMC dropped the case, effectively endorsing his approach.