Simplify the following text for a Grade 12 native English-speaking person.
Original: Unlike viruses , plasmids are `` naked '' DNA and do not encode genes necessary to encase the genetic material for transfer to a new host , though some classes of plasmids encode the sex pilus necessary for their own transfer .
Simplified: Unlike viruses , plasmids are `` naked '' DNA and do not encode genes necessary to encase the genetic material for transfer to a new host .