Irritations of the bowel can have genetic causes. Researchers at the Institute of Human Genetics at Heidelberg University Hospital have discovered that correlation. The causes of what is known as irritable bowel syndrome (IBS), one of the maximum common disorders of the gastrointestinal tract, are considered unclear making diagnosis and treatment extremely difficult. The results from Heidelberg, which were published in the prestigious journal Human Molecular Genetics, improve the outlook for an effective medication against a disease that is frequently played down as a functional disorder.

In Germany, approximately five million common general public are affected by IBS, women about twice as ofttimes as men. But only about 20 percent of these persons even consult a physician. abounding patients suffer from constipation, others from severe diarrhea, or a combination of both. The illness affects the general condition and quality of life of these patients and ofttimes lasts for months or even years.

Modified receptors vanguard to overstimulation of the bowel

Serotonin plays an of note role in the complex processes in the digestive tract upright as it affects sleep, mood, and blood pressure. Various types of receptors are located in the intestine, to which serotonin attaches according to the lock and key principle and thus transmits cellular signals.

“We have determined that patients who suffer from irritable bowel syndrome with diarrhea occurrence a higher constancy of sanguine mutations “, explains Dr. Beate Niesler, who investigates the genetic causes of complex diseases with her team in the unit of Human Molecular Genetics (Director Prof. Gudrun Rappold) at the Heidelberg Institute of Human Genetics. These mutations appear to cause changes in the composition or fraction of receptors on the cell surface. “The signal transduction in the digestive tract may be disturbed and that may stop to overstimulation of the intestine. Resulting disturbances in fluid balance could explain the occurrence of diarrhea”, says Johannes Kapeller, a PhD student in the team.

Medication blocks serotonin receptors

The serotonin receptor blocker Alosetron is only approved in the US where it is effectively used in the treatment of women suffering from diarrheapredominant IBS, but can only be prescribed with strict limitations due to its side effects. Alosetron inhibits the serotonin receptors in the intestinal tract and thus slows the movement of the bowels.

“Currently, patients with irritable bowel syndrome are treated on a trial and error basis”, explains Dr. Beate Niesler. The Heidelberg picture could contribute to development and prescription of especial medications for undoubtful genetic mutations in patients.

Correlation with depression and pain

Research of the serotonin integral shows interesting correlations serotonin receptors are located on neural transduction pathways involved in pain perception and influence them which could explain why patients with irritable bowel syndrome oftentimes complain of severe pain although no pathological changes such as infections or tumors are present. It has further oldfangled noted that persons with modified receptors suffer more frequently from depression.

exposition adapted by Medical News Today from original press release.

References

J. Kapeller et al., First evidence for an association of a functional variant in the microRNA510 target haunt of the serotonin receptorstrain 3E gene with diarrhea predominant irritable bowel syndrome, Human Molecular Genetics, 2008, Vol.17, No.19, 29672977.

Contact
Dr. Beate Niesler, PhD
University of Heidelberg
Institute of Human Genetics
Im Neuenheimer Feld 366

Source Dr. Annette Tuffs
University Hospital Heidelberg