Chiari malformation is a painful skull malformation that affects many small breeds of dogs. This disorder is caused by the premature fusion of skull bones which causes parts of the brain to push through the opening of the back of the skull. This then causes fluid to build up in the spinal cord. It also affects 1 in about 1200 humans.

Researchers at the University of Surrey teamed up with a breeder of Brussel Griffon’s in the Netherlands to study an accidental breeding between her Brussels Griffon and her Australian Terrier.
The four-year study using MRI images of the canine family of Brussels Griffons, showed that with a onetime cross breeding and careful selection of future breeding for head shape, that the inherited problem could be corrected.
The resulting study, published in the PLOS journal, resulted in the Surrey researches teaming up with the geneticists at the University of Montreal to link the results with the dog genome.
What is promising is that the study will be linked to studies in humans, offering hope to the people who are affected by this disorder.
It is interesting to note that backcrossing a breed is not a new concept. It has been done with Dalmatians in an attempt to lower high uric acid in Dalmatians. Another goal of the backcrossing was to decrease the level of deafness found in Dals.
http://www.dogheirs.com/dogheirs/posts/58-chiari-malformation-and-syringomyelia-symptoms
http://www.ninds.nih.gov/disorders/chiari/detail_chiari.htm
http://www.dalmatianheritage.com/about/schaible_research.htm