The positions of three restriction fragment length polymorphisms on chromosome 4 relative to known genetic markers.

A library of DNA sequences cloned in lambda phage has been prepared from DNA of chromosomes sorted by cytofluorimetry to give enrichment for chromosome 4. Five sequences have been assigned to chromosome 4 using a panel of hybrid cells, and each has been localised relative to a translocation breakpoint at 4q26. Each of the probes gives a Southern blot pattern which indicates that it does not cross-hybridize with sequences found on other human chromosomes. Three of the probes reveal frequent restriction fragment length polymorphisms (RFLPs) and are useful for linkage analysis.