Limitations of chromosome classification by multicolor karyotyping

Multicolor karyotyping technologies, such as spectral karyotyping (SKY) (Sc hrock et al. 1996; Liyanage et al. 1996) and multiplex (M-) FISH (Speicher et al. 1996), have proved to be extremely useful in prenatal, postnatal, an d cancer cytogenetics. However, these technologies have inherent limitation s that, in certain situations, may result in chromosomal misclassification. In this report, we present nine cases, which fall into five categories, in which multicolor karyotyping has produced erroneous interpretations. Most errors appear to have a similar mechanistic basis.