Spectral Karyotyping (SKY)
Spectral karyotyping (SKY) is a molecular cytogenetic technique that allows observation of all chromosomes simultaneously, with each chromosome painted in a different color. SKY, developed in 1996, is based on the hybridization of collections of chromosome-specific FISH probes labeled with different fluorochromes or fluorochrome combinations, allowing the discrimination of each of the 24 different human chromosomes. Visualization is aided by a combination of fluorescence microscopy with a specialized imaging system and advanced data analysis methods for reconstruction of spectral information.
Because chromosomal aberrations can be recognized more easily, aberrations appear as missing or additional chromosome pieces or as chromosomes carrying two or more colors. SKY has found routine applications in many areas of cytogenetics and cytology where traditional banding techniques are not sufficiently accurate.
SKY enables the visualization of individual chromosomes in metaphase or interphase cells and the detection of subtle chromosomal aberrations, including marker chromosomes, small translocations, complex rearrangements and minute structural abnormalities, with improved sensitivity and specificity.