Clinical applications of primed in situ labelling (PRINS) rapid identification of a marker chromosome in a fetus.

Abstract

Marker chromosomes pose a serious problem in clinical cytogenetic diagnosis since the conventional banding analyses are often not useful in identifying their origin or composition. In the absence of information, counseling as to the clinical significance and prognosis is difficult, especially in prenatal diagnosis. With the introduction of fluorescence in situ hybridization (FISH) marker identification has became feasible. However, FISH is relatively time-consuming and expensive. In an effort to overcome these disadvantages, we have used primed in situ labelling (PRINS) technique as an alternative. Presented here is one case in which PRINS was useful in rapidly identifying the origin of a marker chromosome detected on amniotic fluid chromosome analysis. Based on our experience with this case and others, we propose that PRINS can become a viable and cost effective alternative to FISH and is as reliable as FISH in terms of accuracy, specificity, and sensitivity.