Sam Rillim (Letters, July 31) was very loud in attacking medical research but remarkably quiet in telling us what we should use instead of animals to give hope to people with serious illnesses.

I would be interested to hear how he plans to replicate a beating heart, blood system and breathing lungs and the way these function together.

These are just some of the necessities required when studying life-threatening conditions.

A survey conducted by the British Medical Association found that 19 out of 20 doctors agreed animal research has aided medical progress.

The BMA made an official statement, which concluded: "We believe animal experimentation is necessary at present to develop a better understanding of diseases and how to treat them, but believe that, where possible, alternative methods should be used."

The Department of Health includes some extensive information on animal research on its web site.

The 30-page Memorandum For The House Of Lords Committee On Animals In Scientific Procedures contains complete and thorough explanations of animal research.

Its introduction states: "Research is essential for progress and research on animals has contributed to almost every medical advance of the past century.

"The NHS would not be able to function effectively were it not for the availability of medicines and treatments that have been developed or validated through research using animals. The public health is the ultimate beneficiary of medical research using animals."

Seriously Ill for Medical Research (SIMR) has a very simple message: For patients' sakes, let animal research continue.

We support the humane use of animals and genetic technology where necessary in medical research.

Our members suffer from illnesses such as cancer, heart disease, diabetes, asthma and arthritis.

To become a Friend (which is free) or for further information, please write to SIMR, PO Box 504, Dunstable, Bedfordshire LU6 2LU, log on to the web site simr.org.uk or email info@simr.org.uk

-Thomas Bromley, SIMR Executive Secretary