U.S. Department of Health and Human Services

Genetics and Biochemistry Branch

Rafael Daniel Camerini-Otero, M.D., Ph.D., Chief


Genetics and Biochemistry Section

Rafael Daniel Camerini-Otero, M.D., Ph.D.

The Genetics and Biochemistry Section studies the biochemistry, molecular, and cell biology of meiotic (homologous) recombination in mice and humans. Our focus is on understanding the biology of genetic recombination and to devise new strategies to manipulate complex genomes in vitro and, in the future, in vivo. Specific projects include biophysical and structural studies of proteins, protein domains and DNA-protein complexes involved, gene rearrangements in eukaryotes and, most recently, mouse and human meiosis and evolutionary genomics. Current interests include the study of Spo11, the protein responsible for the hundreds of developmentally programmed breaks in meiosis, what determines where these breaks are made and where crossovers are located, how homologous chromosomes find each other and how meiosis has shaped the sex chromosomes.

Genome Dynamics Section

Peggy Hsieh, Ph.D.

The Genome Dynamics Section focuses on a highly conserved DNA repair pathway, DNA mismatch repair. Mismatch repair targets base pair mismatches that arise through DNA replication errors, homologous recombination, and DNA damage. Inactivation of mismatch repair results in a large increase in the rate of spontaneous mutation and is associated with both sporadic and hereditary cancers. The Hsieh group utilizes biochemical, structural, and cell biological approaches to study mechanistic questions concerning mismatch excision repair and the cellular response to DNA damage.

Protein Biogenesis Section

Harris D. Bernstein, Ph.D.

The Protein Biogenesis Section studies protein secretion in both pathogenic and non-pathogenic bacteria. We are continuing to pursue a long-term interest in understanding the mechanism of secretion by the autotransporter (“type V”) pathway, which is widely used by pathogenic Gram-negative bacteria to secrete virulence factors. We have also recently begun to study protein secretion in the Bacteroides, a genus of commensal bacteria that constitute a major component of the human gut microbiome.