Public HealthMaternally Inherited Neurological Disorder In Golden Retriever Dogs Is Caused By A Mutation In Mitochondrial DNA
Sensory ataxic neuropathy (SAN) is a recently identified neurological
disorder in Golden Retriever dogs with onset during puppyhood. Affected
dogs
move in an uncoordinated manner and have sensory deficits. Researchers
from the Swedish University of Agricultural Sciences, Uppsala University
and
the Karolinska Institutet have now revealed that SAN is caused by a
mutation in mitochondrial DNA. The study is published May 29 in the
open-access
journal PLoS Genetics.
The researchers were able to trace back all affected offspring on the
maternal side, over more than 10 generations, to a female that lived
during the
1970s. This implied a maternal inheritance, which was confirmed by the
identification of a one base pair deletion in the mitochondrial tRNA-Tyr
gene.
Further analyses revealed that the mutation leads to mitochondrial
dysfunction, which in turn causes a progressive loss of neurons.
The researchers showed that about five percent of the current Swedish
Golden Retriever population carries the mutation causing SAN. The
identification
of the mutation now allows genetic screening tests to identify carriers
and prevent the mutation being transmitted to further generations.
"This is a good example of how a close collaboration between clinicians
and geneticists led to a rapid detection of a harmful mutation that can
now
be eliminated from this dog population to reduce suffering and disease,"
said co-author Karin Hultin Jē¤derlund. The study also provides a new
animal model for similar mitochondrial disorders in humans, said co-author
Izabella Baranowska, and could potentially be used for testing therapeutic
approaches.
CITATION:
"Sensory Ataxic Neuropathy in Golden Retriever Dogs Is Caused by a Deletion in the Mitochondrial tRNATyr Gene."
Baranowska I, Jē¤derlund KH, Nennesmo I, Holmqvist E, Heidrich N, et al. (2009)
PLoS Genet 5(5): e1000499. doi:10.1371/journal.pgen.1000499
Plos Genetics