Modifiers matching mutation:

• genetic,
• common,
• complex,
• severe,
• mild,
• large,
• null,
• local,
• structural,
• rare,
• individual,
• undesirable,
• chromosomal,
• somatic,
• simple,
• neutral,
• visible,
• random,
• major,
• spontaneous,
• gross,

Simple categories matching null:

• value,
• mutation,