select subgraph from graph

Dear All,

i have a graph such as

W = [.41 .99 .51 .32 .15 .45 .38 .32 .36 .29 .21];
DG = sparse([6 1 2 2 3 4 4 5 5 6 1],[2 6 3 5 4 1 6 3 4 3 5],W)

i need to select subgraph for only some nodes such as [6,2,4]

thanks in advance hassan