How to get a list of row names/indexes within the same clustergram in all the different clustergroupd?

I have a large clustergram- CG_gene_data=clustergram(gene_data,'RowLabels',gene_list,'ColumnLabels',specieslist,'Colormap',redbluecmap,'Cluster','COLUMN'); I need a matrix of the indexes/row labels for each of my clustergroups in this large clustergram. for example: (cluster 1) first row in my new matrix=['gene_label1,'gene_label5] (cluster 2) 2nd row in my new matrix=['gene_label22','gene_lable45','gene_label78']

I can't use the clusterGroup(CG_all_lpp_data,cg_index,'row') because it retrieves data of only one clustergroup in my clustergram. Thank you, Mor