Giuseppe Attardi, the California Institute of Technology researcher who identified all the genes in human mtDNA and uncovered the mitochondrial genome's role in degenerative diseases and aging, died Saturday (Apr 5), according to the university. He was 84 years old.

Caltech said that Attardi died at his Altadena, CA home but the university did not indicate a cause of death.

Attardi joined the faculty at Caltech in 1963 and established his laboratory at forefront of mitochondrial genome research. Over his lengthy career at Caltech, Attardi was the first to show that mtDNA produced mRNA, a molecule essential to nuclear DNA translation. He also developed a method for stripping a healthy cell of its mtDNA, replacing it with the mutated mtDNA of patients suffering from diseases, such as mitochondrial encephalopathy.

According to ISI, Attardi published more than 200 scientific papers throughout his career, including several well-cited Nature and PNAS papers as well as his 1988 treatise on the biogenesis of mitochondria published in the Annual Review of Cell Biology. That work has been cited almost 900 times.

Attardi was born in 1923 in Vicari, a small town in Southern Italy. He earned his MD in 1947 from the University of Padua and remained there as a professor of for nearly ten years, before arriving at Caltech at the end of the 1950s on a Fulbright scholarship.

Attardi is survived by his wife Anne Chomyn, a researcher at Caltech, daughter Laura, who is an oncologist at Stanford University, son Luigi, and grandson Marcello.