A Simple Method to Establish Metaphase Chromosomes from Individual Zebrafish Embryos

Cytogenetic approach based on metaphase chromosomes established from dividing cells enables direct microscopic visualization of individual chromosomes, a powerful technique to investigate aneuploidy, chromosome aberrations, and genomic instability. In this study, we describe a simple method based on direct blocking of metaphases in individual zebrafish embryo and dropping slides with temperature changes, water vapor, and acetic acid treatment to increase the metaphase diameters. We demonstrate that well-separated metaphases could be established from single zebrafish embryos using this method. Our method could be further adapted for the analyses of DNA damage, chromosome aberrations, and genomic instability using zebrafish and other teleost models.