Balanced well. Animals with the duplication are WT. Animals which have lost the duplication have a hermaphrodite gonad and intestine (they are self-fertile); the rest of the body is male.

Intersexual self-fertile XX hermaphrodites with Smg (protruding vulva) phenotype. Grows poorly, does best at 20C. Class B1 allele of tra-1 combined with smg-2(NMD), useful for selection of modifiers. Reference: Zarkower et al. (1994) PMID: 7520378