High resolution morphological analysis of in situ human chromosomes

The results showed a package morphology in samples fixed with glutaraldehyde, mainly due to the high capacity of the fixative to strongly crosslink the proteins. In contrast, the fibrillar structure seen in cryosections fixed with acetic acid/methanol is due to the propensity of the fixatives to extract and remove proteins. We propose that in situ chromosomes fixed with glutaraldehyde and then osmicated are a good model for studying the inner structure of chromosomes by using high resolution scanning electron microscopy.