Figure 6.
Screen for mutations that fail to complement Su(Kpn) mutations. Males were mutagenized with EMS and crossed to balancer females (cross I). Male progeny heterozygous for a mutagenized third chromosome were mated to females heterozygous for Su(Kpn)1 (cross II). If no progeny trans-heterozygous for the mutagenized chromosome and Su(Kpn)1 survive, then a putative new allele has been recovered. Male progeny heterozygous for the putative new allele were mated to females heterozygous for Su(Kpn)2 (cross III). If no progeny trans-heterozygous for the putative new allele and Su(Kpn)2 survive, then a new allele has been confirmed. Su(Kpn)i indicates new allele.