Three-stage approach of the Human Genome Project.
- Cytogenetic map
Chromosome banding pattern and location of specific genes by fluorescence in situ hybridization (
FISH
).
- Genetic (linkage) mapping
Ordering of genetic markers.
- Physical mapping
Ordering of
fragments cloned in phage and plasmid vectors;
this gives the actual distance in base pairs between markers.
- DNA sequencing
Determination of nucleotide sequence of each small fragment
and assembly of the partial sequences into the complete genome sequence.