Research after DNA & Liver shunts

A liver shunt is an inherited congenital liver disorder seen in several different dog breeds. Blood from the portal vein is essential for normal liver growth and function. In a dog with a liver shunt, blood from the portal vein does not reach the liver. The liver is essential in removing many toxins formed in the intestines. In the case of a shunt, toxins bypass the filtering processes of the liver to reach the systemic blood circulation and ultimately the brain. One of the most damaging of neurotoxins is ammonia, which when it reaches the brain disrupts normal brain function. In Schnauzers a liver shunt is found quite often as well. Back in 1995 Schnauzers were already found to be predisposed for this disease.

Diagnosing a portosystemic shunt is done in Utrecht by measuring ammonia levels in the blood. Blood from the jugular vein will be drawn after 12 hours fasting. In Utrecht definitive diagnosis will be obtained by either ultrasonography or CT-scan. Another method used worldwide is measuring bile acid concentrations.

The Companion Animal Clinic at Utrecht University (Netherlands) has conducted extensive research into the diagnosis, associated metabolic processes, and palliative and corrective treatments, including surgical correction. Starting January 2008, Frank van Steenbeek has started the molecular genetic analysis of shunts in the genomics lab of Utrecht University.

State-of-the-art molecular genetic research is currently being used to identify these yet-to-be-discovered genes causing liver shunts in Cairn terriers. With these results other breeds will be used to determine whether the same genes cause shunts in these breeds. The long-term goal of this effort is to develop a genetic test for identifying (unaffected) carriers among different dog breeds before they are bred and produce shunt-affected puppies and more unaffected carriers of shunts. By making intelligent combinations and meticulously following up on their offspring, it is possible to rid the population of disease genes without totally eliminating truly important dogs from breeding.

The research can only progress if DNA from Schnauzers affected with shunts and their parents is available for analysis. Submitting DNA requires courage and effort on the parts of breeders and owners. Please take the time to participate in this important research if you have an affected dog or own parents of an affected Schnauzer. All individual information will be used strictly confidentially by the researchers and not be disclosed to any other party. If you have a shunt-affected dog or parents of one, DNA can be isolated from blood collected in EDTA-coated tubes, generally available from your veterinarian. If you wish to submit Blood/DNA, please contact Frank van Steenbeek (f.g.vansteenbeek@uu.nl) for instructions on how to do this.

Department of Clinical Sciences Companion Animals

Faculty of Veterinary Medicine

Utrecht University, The Netherlands

Yalelaan 104

3584 CM Utrecht, The Netherlands