INTERACTIVE COMPUTER-AIDED ASSIGNMENT OF MULTIPLE PROBES TO CYTOGENETIC BANDS BY SIMULTANEOUS DUAL-COLOR FLUORESCENCE IN-SITU HYBRIDIZATIONAND DAPI BANDING

A macro function was developed to run in conjunction with the popular image analysis package NM Image, to allow simultaneous determination o f mapping positions of one or two separate probes with respect to cyto genetic bands by dual color fluorescence in situ hybridization (FISH) and DAPI banding, and by determination of their fractional distance fr om pter (FLpter). In order to allow maximal flexibility, a user-define d line along the chromosome is used for measurements, Algorithms were developed to detect the ends of the chromosome and the cytogenetic ban ds, Results of the analysis are presented ia graphical form, comprisin g a display of the DAPI intensity along the chromesome, the positions of the probe(s), the locations of bands as determined by analysis of t he second derivative of the DAPI intensity profile, and a standard ide ogram of the chromosome for comparison, The approach was validated and compared to visual assignment of probes to DAPI bands using the cosmi d clone PYGM, which has been previously mapped to chromosome 11q13, an d has been used as a landmark for mapping of other probes (3). (C) 199 6 Wiley-Liss, Inc.