It is with great sadness that we announce the passing of our friend and colleague, Dr. David B. Busch who succumbed to leukemia on April 11 at the age of 48 years.

David was a remarkable, intelligent, and dedicated person. He received an undergraduate degree in biochemistry with distinction in 1974, a masters in biophysics in 1976 and Ph.D. in biophysics in 1980 all at the University of California, Berkeley. His Ph.D. work was performed under the guidance of Nobel prize winner, Dr. Donald Glaser. He then earned an M.D. degree in 1982 in a special 2 year program for Ph.D's at the University of Miami. This was followed by residencies in anatomic and clinical pathology at the University of Wisconsin in Madison which culminated in his becoming a Diplomate of the American Board of Pathology in 1986. The same year he joined the Armed Forces Institute of Pathology in Washington, DC where he spent his professional career as a Radiation Pathologist.

His early DNA repair work was focused at discovering DNA repair mutants in Chinese hamster cells. He performed large scale isolation and characterization of UV sensitive DNA repair mutants of these CHO cells. This work led to the discovery of rodent cells that were homologues of several human diseases: xeroderma pigmentosum (XP) complementation group D (ERCC2), group B (ERCC3), group F (ERCC4), group G (ERCC5), Cockayne syndrome group B (ERCC6) and Fanconi anemia group G (UV40). Each of these cell lines was pivotal in the efforts by several laboratories to clone the corresponding these human genes.

Over the last 25 years David had an extremely successful interaction with Dr. Larry Thompson at Lawrence Livermore National Laboratory. Although Larry was not a formal member of David's Ph.D. thesis committee, Larry provided David with guidance and considered him to be a truly outstanding graduate student. David always seemed to understand everything and was able to set high goals for himself and meet them. David ensured that mutants were still being sent to Livermore by technicians after he had gone to medical school.

When the Glaser laboratory closed because of loss of funding, Larry maintained David's mutant collection in liquid nitrogen for about a decade until David established his own laboratory in Washington, DC. David then systematically analyzed the complete collection and produced a series of publications that involved collaborations with scientists in the Netherlands, in Texas, and other places. This extended accomplishment was a reflection of David's thorough, persistent research style. Larry's lab benefitted immensely from David's mutants. Some of the mutant lines have been in a national repository for many years and will continue to serve numerous investigators indefinitely.

When Dr. Kenneth Kraemer first met David, Dr. James Cleaver had been performing clinical diagnostic tests for XP patients in the US. New Federal regulations made it difficult for Jim to continue this work in a research lab. David, who was a card-carrying pathologist in a distinguished institution that was familiar with Federal regulations, stepped in to perform this valuable service.

David put his heart and soul into this important work. He began by offering testing for XP and then expanded to test for Cockayne syndrome and trichothiodystrophy. He tested samples from several hundred patients over the years. These results have changed many people's lives. The Kraemer laboratory and others around the world are currently performing further analysis on many of these cells and will be studying them for years to come.

The laboratory work was only part of his effort. David soon realized that the people whose cells he tested were searching for assistance as well. He regularly visited Camp Sundown, a camp for XP patients, and a similar group for families with Cockayne Syndrome. He brought his cats and his good humor to cheer up those affected with XP and CS. He will be greatly missed.

Sincerely,
Kenneth H. Kraemer, M.D., Bethesda, MD James E. Cleaver, Ph.D., San Francisco, CA Larry H. Thompson, Ph.D., Livermore, CA

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Of additional interest: David Busch maintained a website "Myelodysplasia and me" that chronicled the unfortunately rapid course of his disease beginning from diagnosis as a precancer in November 2000 David was fond of exotic cats as can be seen in his other website: "About Jadzia Cattery and Emony's Exotic Cats" which describe his efforts to breed exotic Norwegian forest cats and Canadian lynxes David Busch prepared an educational CD "Xeroderma Pigmentosum and Cockayne Syndrome - A Multimedia Overview" which includes video clips of patients and researchers . He also made two educational videotapes: "Cockayne Syndrome (CS) and Xeroderma Pigmentosum (XP)" and "DNA Repair Disorder: X-Ray Sensitivity Disorder