My work is dedicated to understanding the functional consequences of genetic variation in humans spanning multiple areas of human molecular genetics that include (i) X chromosome inactivation, (ii) Y chromosome- mediated sex determination, (iii) evolution and population genetics of human sex chromosomes, (iv) the molecular genetics of genomic instability and DNA repair, (v) the relationship between genomic instability and cancer susceptibility, and (vi) the molecular and genetic epidemiology of colorectal and breast cancer. I am internationally recognized for the work that led to cloning of the gene mutated in Bloom’s syndrome, BLM, and for the on-going characterization of the gene and its protein product in the realm of replication fork stability and regulation of homologous recombination repair. Over the last 15 years, I have developed expertise in the analysis of patient groups at high risk of developing colorectal cancer, association studies of single nucleotide polymorphisms (SNPs) and rare variants that are associated with colorectal cancer risk, and bioinformatics analysis of high throughput data from genetics and genomics platforms. I have extensive experience in performing and analyzing DNA sequencing and genotyping results and am expert in the use of statistical methods for association analysis.
I lead a project to identify and characterize the molecular cancer genetics of colon and rectum in African Americans, which has been supported by a grant from the NCI Center to Reduce Cancer Health Disparities (U01CA153060). The goals of this project are to understand the molecular and genetic mechanisms that mediate risk of colorectal cancer and to examine mechanisms of carcinogenesis. Central to this effort is the biological specimens and clinical data accumulated by Chicago Colorectal Cancer Consortium (CCCC).
Established and implemented by myself and Xavier Llor while we were both in Chicago, the CCCC focuses on the biological determinants of health disparities in colorectal cancer. We are investigating mechanisms leading to the excess right-sided colon cancer and early-onset colorectal cancer in the African American population.
Over my 35-year career, so far, I have gained a lot of experience in mentoring and supervising young scientists, including 7 graduate students and 14 post-doctoral fellows. I have mentored 8 career scientists, supervised 26 technicians and technologists, and trained 44 undergraduate or rotating graduate students, medical students, or high school students. These trainees have come from a wide variety of ethnic backgrounds, including persons of Hispanic and Native American ancestry. I am committed to the advancement of much greater diversity in the scientific community at all levels of the career hierarchy.
I lead the Cancer Biology Program in the University of Arizona Cancer Center.