A similar approach looking for genetic modifiers using a Drosophila model of FXTAS found 18 genes that genetically modulate CGG-associated neurotoxicity in flies, particularly Prosbeta5 (PSMB5), since knockdown of PSMB5 suppressed CGG-associated neurodegeneration in the fly but also in human cells [83]. Here, PSMB5 is linked to fragile X-associated tremor/ataxia syndrome.