Summary: Reciprocal translocation, well characterized, very stable. Effective balancer for left portion of LG I through unc-13, nearly all of LG X from right end to around dpy-3. szT1(I) is large segment of LG X (right) translocated to LG I, disjoins from normal LG I. szT1(X) is LG I (left) translocated to fragment of LG X (left), disjoins from normal LG X.
Handling: Easy to manipulate. Lon-2 szT1 males mate well. Rare exceptional progeny carry one half-translocation as a complex free duplication. Gives rise spontaneously to rare apparent lethal mutations that may represent fusion of szT1(X) and the normal X. Shows threefold enhanced recombination frequency immediately adjacent to right of LG I breakpoint and about twofold enhanced frequency in the unc-101 - unc-54 interval.