Related Experiment Video
Updated: Jun 24, 2026

Microsatellite DNA Genotyping and Flow Cytometry Ploidy Analyses of Formalin-fixed Paraffin-embedded Hydatidiform Molar Tissues
Published on: October 20, 2019
Tetrasomy 12p (Pallister-Killian syndrome): difficulties in prenatal diagnosis
1Institut für Humangenetik, Universitätsklinikum Giessen-Marburg, Germany.
Purpose:
We report a rare case of Pallister-Killian syndrome diagnosed prenatally with increased nuchal translucency during screening for trisomy 21.
Materials And Methods:
Echografic and postmortem examination of the fetus, G-banded chromosome and FISH analysis on short- and long-term chorion villous sampling (CVS) culture.
Results And Discussion:
Cytogenetic analysis revealed a supernumerary isochromosome 12p after long-term culture whereas a normal cell line was detected in short-term culture only. Sonografic examination in 17-weeks' gestation showed further increase of the NT and the additional presence of brachymelia, diaphragmatic hernia and a marked dextroposition of the heart. Termination of the pregnancy was performed. The cases of PKS karyotypically confirmed on CVS are reviewed, and cytogenetic and sonographic aspects of the prenatal diagnosis of PKS are discussed.
Related Concept Videos
Karyotyping
Genomic Imprinting and Inheritance
The expression of some genes depends on which parent passed the gene to the offspring, through a phenomenon known as...
Meiosis I
Meiosis vs. Mitosis
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
Nondisjunction
Nondisjunction
