Table 1.

Analysis of the [Het-s^*] → [Het-s] transition

	Number of strains that have gained the [Het-s] phenotype
	Donor strain = [Het-s] Recipient strain = [Het-s*]	Donor strain = [Het-s] Recipient strain = het-s°	Donor strain = het-s° Recipient strain = [Het-s*]
Absence of cycloheximide	17/17	0/12	0/10 0/7†
Presence of cycloheximide	13/13	nd	nd

Conditions were as described in Materials and Methods, Fig. 2, and in the text. The values are given as the ratio between the number of strains that have gained the [Het-s] phenotype and the number of tested recipient strains. nd, not done. 

^†In this experiment, the het-s° strain was first fused to a [Het-s] strain then pieces of mycelium of the het-s° strain were used to regenerate mycelia that were used as donors.