HIGH-MOLECULAR-WEIGHT DNA FROM NUCLEATED ERYTHROCYTES FOR USE IN PULSED-FIELD GEL-ELECTROPHORESIS (PFGE)

Nucleated erythrocytes of lower vertebrates provide a source of genomi c DNA that can be used in pulsed-field gel electrophoresis (PFGE) stud ies. Difficulties reported in the preparation of chicken erythrocyte D NA for analysis by PFGE suggest that the presence of hemoglobin iron m ay result in iron-mediated DNA degradation. We report here modificatio ns to the procedures established for isolation of high molecular weigh t DNA from mammalian cells. By increasing the volume of buffers and ex tending the incubation periods to allow for the removal of hemoglobin iron, we have successfully prepared channel catfish erythrocyte DNA su itable for analysis by PFGE.