Possible Clues:

• 'It'd turn your stomach, that insect, just for a change (6)'
• Mongrel incorporating a new genetic variation
• Cell that carries a mutation of a gene
• Changed man?
• Organism with characteristics resulting from gene changes
• "X-Man" sort
• Like some teenage turtles
• Sci-fi baddie
• Cell that carries an alteration of a gene
• Wolverine of Marvel Comics, e.g