A Sorghum propinquum BAC library, suitable for cloning genes associated with loss-of-function mutations during crop domestication

A large insert Sorghum propinquum BAC library has been constructed to analy ze the physical organization of the sorghum genome and to facilitate positi onal cloning of sorghum genes and QTLs associated with the early stages of grain crop domestication. This library was established from 12 different li gations using high-molecular-weight DNA generated from either one cycle or two cycles of size selection. This library consists of 38 016 BAC clones wi th an estimated average insert size of 126 kb and coverage of 6.6 genome eq uivalents. The 6.6 genome-equivalent BAC library of S. propinquum provides a 99.7% probability of finding one or more BACs that contain genes of inter est. Twenty mapped DNA probes, ten homologous and ten heterologous, were us ed to screen the library, and 121 positive clones were identified, 6.05 per locus or 6.37 per probe.