Chromatin Threads from Cell Nuclei

Abstract

MUCH work has been done during the last few years by Mirsky and Ris^1,2 and by Claude arid Potter³ on thread-like bodies isolated from cell nuclei, such as those of carp erythrocytes and calf thymus. These bodies are sometimes called chromatin threads³ and sometimes, as by Mirsky and Ris, more boldly and specifically “isolated chromosomes". In this Laboratory we have repeated so far as possible from the published data the work described by these authors. We have not been concerned in the first instance with biochemical studies⁴ of these threads, but have tried to find if they can properly be regarded as chromosomes. The purpose of this note is to summarize the work leading to our conclusion that the threads are not isolated chromosomes, but are complex fragments of drawn-out nuclei.