• Analysis of the human DNA sequence was completed in 2001, allowing scientists to study the many genes that influence pain perception.
• Variations in individual genetics may be one explanation why certain members of the community appear to be more sensitive to pain than others e.g. fibromyalgia, chronic tension headache, irritable bowel syndrome etc
• Techniques have been developed that allow the study of transmission and modulation of pain. By looking at individual gene mutations, explanations for pain resistance and pain susceptibility have been found. Gene therapy for painful conditions is also being studied.

New Techniques

• The study of genetics has been greatly facilitated by the use of experimental mice. Mice that have had an extra gene inserted into their genome are known as transgenic mice, and those where a gene has been inactivated are known as knockout mice.
• Antisense technology has allowed scientists to block the action of certain genes by using extra complimentary strands of messenger RNA (mRNA) that bind to existing strands of mRNA blocking their action.

Pain Specific Genes

• Nearly 200 molecules have been found to be involved in the processing of pain, and the genes responsible for producing these molecules have also been studied.
• Differences in the response to morphine has been linked to the genes that produce an enzyme called cytochrome P450.
• Other genes are being studied that control molecules that control pain processing e.g. neurotransmitters, pain receptors, metabolic enzymes, ion channels, inflammatory mediators, nerve growth factors, and intra-cellular messengers.
• Future developments may have an impact in the following areas - morphine sensitivity in cancer pain, pain sensitivity in fibromyalgia, chronic prostatitis, chronic pelvic pain, herniated lumbar discs.

Gene Therapy

• Side effects from existing pain drugs has promoted the search for new molecular targets.
• Transplantation of engineered cells that produce pain relieving substances has been pioneered in animals in the treatment of neuropathic pain.
• Damaged nerve cells have been injected with an externally engineered gene that allows the nerve cell to repair in experimental models of shingles and post herpetic neuralgia.
• The main issues with gene therapy are the long term effects of the treatment are not yet known, and the research methods are not yet licensed for use in humans.