Leroy Hood, American biologist and academic
Leroy "Lee" Edward Hood (born October 10, 1938) is an American biologist who has served on the faculties at the California Institute of Technology (Caltech) and the University of Washington.

Hood has developed ground-breaking scientific instruments which made possible major advances in the biological sciences and the medical sciences. These include

the first gas phase protein sequencer (1982), for determining the sequence of amino acids in a given protein;

a DNA synthesizer (1983), to synthesize short sections of DNA;

a peptide synthesizer (1984), to combine amino acids into longer peptides and short proteins;

the first automated DNA sequencer (1986), to identify the order of nucleotides in DNA;

ink-jet oligonucleotide technology for synthesizing DNA and

nanostring technology for analyzing single molecules of DNA and RNA.The protein sequencer, DNA synthesizer, peptide synthesizer, and DNA sequencer were commercialized through Applied Biosystems, Inc.: 218  and the ink-jet technology was commercialized through Agilent Technologies.

The automated DNA sequencer was an enabling technology for the Human Genome Project. The peptide synthesizer was used in the synthesis of the HIV protease by Stephen Kent and others, and the development of a protease inhibitor for AIDS treatment.Hood established the first cross-disciplinary biology department, the Department of Molecular Biotechnology (MBT), at the University of Washington in 1992, and co-founded the Institute for Systems Biology in 2000. Hood is credited with introducing the term "systems biology", and advocates for "P4 medicine", medicine that is "predictive, personalized, preventive, and participatory." Scientific American counted him among the 10 most influential people in the field of biotechnology in 2015.Hood was elected a member of the National Academy of Engineering in 2007 for the invention and commercialization of key instruments, notably the automated DNA sequencer, that have enabled the biotechnology revolution.