Compositions and methods related to transgenic AHAS-inhibiting herbicide resistant soybean plants are provided. Event 127 soybean plants having a mutated AHAS coding sequence which imparts tolerance to an AHAS-inhibiting herbicide are provided. The event 127 soybean plants having the event 127 nucleic acid molecule at the identified chromosomal location may comprise genomic/transgene junctions having at least the nucleic acid sequence of SEQ ID NO: 5 and/or 6. The characterization of the genomic insertion site of the event 127 provides for an enhanced breeding efficiency and enables the use of molecular markers to track the transgene insert in the breeding populations and progeny thereof. Various methods and compositions for the identification, detection, and use of the event 127 soybean plants are provided.