Fig. 1

Sample-to-sample network analysis using BioLayout, showing relationships between gene expression patterns of mitral valve samples. Nodes (spheres) represent samples and edges (lines between samples) show a correlation between the expression profiles of samples of greater than 0.98. Similar samples are placed close together in the network. Each image shows the same network with nodes coloured based on different variables. a. Nodes are coloured by sex of the dog from which the valve was removed. Red – female; blue – male. b. Nodes are coloured by grade of MMVD disease found in the valve. Green − normal valves; Orange – Grade 3 diseased valves; red – Grade 4 diseased valves. c. Samples from CKCS diseased valves are separated from other samples. Green − normal valves; blue − non-CKCS diseased valves; dark red − CKCS diseased valves