TABLE 3

Evidence that transparent mutations of independent origin map to the cya-8 region left of adh in linkage group VII from crosses of adh nic-3 (nontransparent) × adh+ nic-3+ (transparent)

Crossovers
Singlesb
Cross no.aParentalscya-8-adhadh-nic-3Doubles
986b431881
118426410
1190271231
1273515110
133536260
134719590
135335310
135731360
136019400
Totals28756452
  • a Each of the nine crosses was adh nic-3 × a phenotypically wild-type heterokaryon carrying nuclei of the transparent parent in combination with those of the inactive mating-type helper-1 strain am1 ad-3B cyh-1. Scoring of adh and nic-3 was done only among the nontransparent progeny. Each of the nine transparent strains used in these crosses originated independently from a separate cross that involved a different easUCLA parent of single-ascospore origin. The easUCLA parents were from seven different crosses. Allelism of the newly arisen transparent mutations to cya-8 was also indicated by barrenness when they were crossed with cya-8 (P9178). Recombination frequencies from the pooled data are cya-8 15% adh 12% nic-3.

  • b Phenotypically transparent progeny were known to be cya-8 in cross 986 and were inferred from their map position to be at the same locus in the other crossses. The transparent mutation in cross 986 was isolation no. P9178 (FGSC 4523), which was designated cya-8 and was used for the original mapping.