Current Research and Scholarly Interests
To understand how cells repair DNA damaged by ultraviolet radiation (UV), we identified and characterized UV-damaged DNA binding activity (UV-DDB). The p48 subunit of UV-DDB is mutated in xeroderma pigmentosum group E. UV-DDB enhances nucleotide excision repair while suppressing UV-induced mutagenesis.
To understand how cells repair DNA damaged by ionizing radiation, we study the non-homologous end joining pathway, which repairs double-strand breaks produced by ionizing radiation and V(D)J recombination. We are currently studying the joining reaction with purified proteins to determine how the DNA double-strand breaks are repaired.
To interpret the massive amounts of data in gene expression profiles, we invented the widely used algorithms SAM (Significance Analysis of Microarrays) and PAM (Prediction Analysis of Microarrays).
We are collaboratively developing a point-of-care device to measure blood ammonia from a single drop. The device will facilitate diagnosis and management of elevated blood ammonia, benefiting children with inborn errors in the urea cycle, patients with liver disease, and cancer patients with chemobrain due to elevated ammonia.