MICROGEL ELECTROPHORESIS - SENSITIVITY, MECHANISMS, AND DNA ELECTROSTRETCHING

Based on the treatment of microgels to remove proteins, we speculate t hat proteins may be bound to DNA in the microgels even after electroph oresis. We speculate that some DNA single-strand breaks may be a refle ction of these protein-DNA complexes. We suggest methods to limit such artifacts, and present data demonstrating a lymphocyte DNA double-str and break sensitivity of 12.5 rads and day-to-day reproducibility of m icrogel electrophoresis using these principles. Extending these princi ples, we describe DNA behavior during alkaline and neutral microgel el ectrophoresis based on observations of the stained DNA and its migrati on patterns. During microgel electrophoresis, individual DNA molecules behave as if anchored at one end while the other end is free to migra te in response to the electric field. We capitalize on this behavior b y developing a neutral microgel method to stretch chromosomes.