Ranking genes from cluster map

Question

[Govardhan Anande]

How should I rank the top contributing genes to cluster.

For example : If I use 100 genes from 5 samples to perform clustering, then how can I get the top 20 contributing genes to that cluster.

Thank you in advance.

Answer 1

[Carlo Yague]

If the clustering is build in order to highlight differences between samples, you could define the top 20 genes as the genes with the highest coefficient of variation across samples.

Answer 2

[Jean-Karim Heriche]

A general and widely used indicator is the silhouette.