Biomart Problem.!!

Question

[bioinfo]

I am using a set of human genes, How to find out which gene(s) fall aside the functional 'core by biomart? and how to find out the similarities between these genes through biomart?'

[Neilfws]

You'll have to explain what "fall aside the functional 'core" means - it makes no sense as written. And define a measure of similarity: sequence-based? Or something else?