modifier of variegation enhancer of variegation Typically, g2 is a chromosomal aberration or an insertion. FBcv:0000379 phenotypic_class Genotype g1 is an enhancer of variegation if, and only if, some genotype g2 has a variegated phenotype and the degree of variegation caused by g1g2 is greater than that caused by g2 alone.