The "expert panel" in your article (June 29) apparently states that there is currently little by way of treatment or educational approach that could be recommended to treat autism other than some pharmacological (drug) interventions. This comes as a surprise to me, a research scientist well informed on autism research both at a medical and educational level. I have reached some very different conclusions. I am also aware of the many reports of medical and clinical impairments associated with the condition that can be identified following thorough investigation and treated medically, often with significant improvement.

Biomedical interventions that have been shown to lead to recoveries are often complex, comprised of several interdependent parameters, and carried out over a long period, usually for a minimum of two years. Furthermore, often a biomedical intervention is coupled with an educational programme. Under these conditions, it is simply not possible to use a Random Control Trial (RCT) design to evaluate treatment efficacy.

For the past 60 years the diagnosis of autism has continued to be solely based upon its overt behavioural features. This is surprising because medical experts in the field have long recognised that behind this set of purely behavioural syndromes exists a multitude of possible clinical abnormalities of genetic, metabolic, physiological as well as viral or toxicological origins. On that issue, while the "guidelines" recognise the need for appropriate diagnosis, they omit totally to mention the need for a thorough medical examination of the affected children. This is a tragic omission and casts doubt on the validity of this "expert report" and the knowledge base of its authors. Until we refine autism diagnosis using the "clinical" underlying features, we will simply be stuck in treatment evaluation studies.

Regarding the benefit of medication in autism, the literature in this domain is probably one of the most controversial. Many studies contradict each other and there are very valid reports of considerable side-effects, including deaths, with the use of the drugs Dr Iain McClure's team recommends.

Dr McClure's report disappoints on many fronts, not least because it has missed an opportunity to redefine the condition and influence the emphasis of the research agenda.

Dr Lorene Amet, Principal Scientist, Autism Treatment Trust, 26B Great King Street, Edinburgh.

Bill Welsh suggests that the Medical Research Council has acted shamefully as he asserts it has "not funded the clinical examination of even one child who has become autistic following MMR".

In 2001, the MRC undertook the first comprehensive review of UK research into autism. We carried out this extensive study in response to growing public concern about the greater number of autism cases diagnosed than in the past and a possible link to the MMR vaccine and bowel disorders. The resulting review has steered MRC policy in autism research, and many of the original recommendations it made for research have been met. In contrast to Mr Welsh's accusation, the MRC acted within its remit and as a leader in the field. And it continues to do so. Since 2002, the MRC has invested more than £3.1m to fund research into autism. Current research projects focus on genetics, potential risk factors for developing autism alongside studies into new approaches to treatment and possibly even prevention.

Concerns over the safety of the MMR vaccine, fuelled by Andrew Wakefield's claim in 1998 that autism is caused by the MMR vaccine, have been widely discredited and the co-authors on his original research paper have dissociated themselves from his suggestion. Far from acting shamefully, the MRC continues to invest in research into autism, including a pre-school autism communication trial and a major contribution to the autism genome project. MRC is an influential partner, working with others including Autism Speaks, leading a huge effort to understand this debilitating condition.

Diana Dunstan, Director of Research Management, Medical Research Council, 20 Park Crescent, London.

I read today's letter from Bill Welsh regarding the link between the MMR and autism with sadness. My son has higher-functioning autism diagnosed in March. Like most parents who have autistic children, I would like to know what has caused this. I have asked different medical people about the link between MMR and my son's condition. Most have dismissed it. Some have said there is now evidence and perhaps more research has to be done to prove or dispel this.

I have no confidence in an answer to my questions on autism being provided in the short term. There does not seem to be any haste within the political system to spend the money needed to give the answer that parents want. It seems we would rather spend money on things such as Trident and nuclear power stations.

My son is aged five but I doubt he will ever have any answers as to why he is autistic.

John Henery, 36 Doune Park Way, Coatbridge.