The present disclosure relates in some aspects to methods and compositions for analyzing a target nucleic acid, such as in situ detection of a region of interest in a polynucleotide in a cell or tissue sample. In some aspects, provided herein are circular probes (e.g., dumbbell probes) for analyzing a target nucleic acid, as well as methods comprising an enzymatic treatment to de-circularize unbound or non-specifically bound circular probes. Circular probes specifically bound to target nucleic acids remain intact during and after the enzymatic treatment and can be detected, e.g., via rolling circle amplification (RCA) of the circular probes and detection of the RCA products.