Originally described in 1985, hereditary multifocal renal cystadenocarcinoma and nodular dermatofibrosis (RCND) is a naturally occurring canine kidney cancer syndrome in German shepherd dogs (Lium & Moe, 1985). As the name suggests, RCND is characterised by bilateral, multifocal tumours in the kidney and firm nodules within the skin, thus showing similarity to human BHD syndrome.
The RCND locus was located to a small region on canine chromosome 5 that overlapped with FLCN (Lingaas et al., 2003). The authors described a histidine to arginine mutation (H255R) in exon 7 of canine FLCN that segregated with the disease phenotype. There is also strong evidence that the mutation is homozygous lethal (Lingaas et al., 2003), much like the homozygous phenotypes in the rat and mouse models.
Researchers also observed a loss of heterozygosity within the renal cysts and tumours of juvenile and adult dogs respectively, indicating a tumour suppressor function for FLCN according to the Knudson two-hit hypothesis (Bønsdorff et al., 2008; Bønsdorff et al., 2009).
