A new SNP region in the regulatory region of COLIA1 is associated with bone mineral density in perimenopausal Spanish women

The araC gene in Salmonella typhimurium is autogeneously regulated. Nine non-self-regulated mutants were isolated by selecting for increased expression of an araC-lacZ fusion in the presence of a repressing AraC protein. S1 mapping experiments demonstrated that the effect of the mutations was to increase the amount of araCmRNA in the cell. The 5'-end of the major araC transcript was the same in the wild-type (wt) and mutant strains. DNA sequence analysis showed that all nine mutations occurred m the araC promoter. Two mutations were a G-to-T transversion at position −25, six were a G-to-T transversion at position −47 and one was a single bp deletion at position −83. The data suggest that the mutations have created a new RNA polymerase binding site which enhances transcription from the wt start point.