Direct sequencing of amplified genomic fragments documents N-ras point mutations in myeloid leukemia

A number of different techniques have been utilized to document point mutations in ras oncogenes in leukemic cells, but these approaches are either labor intensive, require relatively large numbers of leukemic cells or provide sequence data for only a limited number of codons. Here we describe a technique for documenting N-ras point mutations that involves the direct sequencing of N-ras genomic fragments that have been amplified in vitro utilizing the polymerase chain reaction (PCR). This technique permits the rapid analysis of a relatively large number of samples. Moreover this approach requires relatively small numbers of cells and provides direct nucleotide sequence information of multiple N-ras codons at a single reading.