Funds are requested for development of a method for obtaining a physical map of any group of specific nucleotide sequences on a sample DNA molecule. The linear positions of the sequences are obtained by observation, using a microscope, of oligonucleotide probes tagged with a fluorescent markers. In the initial development the 48,502 nucleotide long DNA from the bacterial virus lambda is proposed as a model sample DNA, since the complete sequence is known for this DNA. When applied to genomic DNA obtained from human cells, the method has the potential to obtain a map of sequences in the vicinity of any unique sequence in the genome without purification or cloning steps that are required by current technology. It is anticipated that the mapping method would initially be used in the Human Genome Program to determine the relative positions of clones of small segments of the genome; thus, speed the assembly of sequences from these segments into the genomic sequence. However, the same mapping method might later be developed as an diagnostic DNA probe assay with the ability to simultaneously detect multiple genetic defects.National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
