Differential staining of the X-chromosome during meiosis of orthoptera by a silver impregnation procedure.

Differential staining of the X chromosome of Orthoptera, which normally cannot be distinguished from the autosomes during the more condensed stages of meiosis, has been achieved by a silver impregnation procedure involving a pretreatment with 2 x SSC at 60 degrees C. The results suggest that the saline citrate solution preferentially extracts proteins from the X chromosome. This method may be useful for distinguishing chromosome regions composed of facultative heterochromatin in Orthoptera.