Preparation of amniocytes for interphase fluorescence in situ hybridization (FISH)

Although FISH has been used to clarify deletions or structural rearrangements, recent work has focused increasingly on its applications to interphase analysis. This unit describes preparation of uncultured amniotic fluid cells for FISH analysis. Cells are swollen, then slides are prepared using either a cytocentrifuge or standard methods. These are then fixed and permeabilized for subsequent FISH. An Alternate Protocol describes attachment of amniocytes to a glass or plastic surface followed by hypotonic swelling, fixation, and permeabilization for subsequent FISH. Interphase FISH analysis of amniotic fluid cells is also described.