"SEQUENCING THE HUMAN GENOME:
ELUCIDATING OUR GENETIC BLUEPRINT"
The human genome consists of ~3 billion base pairs (bp)
of DNA contained within 24 chromosomes that range in size from ~50 to ~260
million base pairs. Encoded within this DNA are an estimated 25,000 to
75,000 genes and the necessary elements that control the regulation of
their expression. Started in 1990, the Human Genome Project is a coordinated,
international effort to map and sequence the human genome and, in parallel,
that of several well-studied model organisms. The first phase of the Human
Genome Project involved constructing relatively low-resolution maps of
the human genome and refining the approaches for large-scale DNA sequencing.
The second phase has focused on establishing the complete sequence of the
human and other vertebrate genomes as well as beginning to decipher the
encoded information in a systematic fashion. Earlier this year, a major
milestone of the Human Genome Project was reported: the completion of a
‘working draft’ sequence for ~90% of the human genome. In essence, this
reflects the acquisition of preliminary sequence data for virtually all
of the readily clonable human DNA. This sequence will be refined (i.e.,
finished to high accuracy) over the next 2-3 years. The new and powerful
foundation of genetic information is empowering investigators to tackle
complex problems relating to disease, development, and evolution that were
previously unapproachable.