Heterozygotes are WT. Animals which have lost the duplication are Unc and homozygous for rgs-7. Animals which are homozygous for the duplication are dead. Unc is temperature sensitive. vs92 is a 361 bp deletion which removes the 3' splice site of exon 6, all of exon 7 and half of exon 8. All of the deleted region is within the RGS domain.