ASSIGNMENT OF ALU-REPETITIVE SEQUENCES TO LARGE RESTRICTION FRAGMENTSFROM HUMAN-CHROMOSOME-6 AND HUMAN-CHROMOSOME-22

We have employed a pulsed field gel electrophoresis and Alu hybridizat ion approach for identification of large restriction fragments on chro mosome 6 and 22. This technique allows large portions of selected huma n chromosomes to be visualized as discrete hybridization signals. Soma tic cell hybrid DNA which contains chromosome 6 or chromosome 22 was r estricted. with either Notl or Mlul. The restriction fragments were se parated by pulsed field gel electrophoresis (PFGE) and hybridized agai nst an Alu repetitive sequence (Blur 8). The hybridization signals res ult in a fingerprint-like pattern which is unique for each chromosome and each restriction enzyme. In addition, a continuous pattern of rest riction fragments was demonstrated by gradually increasing puls times. This approach will also be suitable to analyze aberrant human chromos omes retained in somatic cell hybrids and can be used to analyze flaw sorted human chromosomes. To this end, our method provides a valuable alternative to standard cytogenetic analysis.