Fig. 5. Model for the generation of sister chromatid gene conversion events. LTGC and LTGC/NHEJ events can be initiated by strand invasion of the broken S2neo gene into the 3′ neo gene on the sister chromatid, with repair synthesis primed by the invading end. (A) In an LTGC event, repair synthesis continues into the downstream S2neo gene and is followed by homologous annealing of the newly synthesized strand to the end of the broken chromatid. (B) In an LTGC/NHEJ event, repair synthesis terminates downstream of the neo⁺ gene and is followed by NHEJ of the newly synthesized strand to the end of the broken chromatid. See text for details.