Dr. Ralf Krahe
The University of Texas MD Anderson Cancer Center
Department of Genetics
- Human and molecular genetics
- Cancer genetics
Research in my laboratory focuses on the identification and characterization of human disease genes and their mutations/variants, including inherited cancer syndromes (Li-Fraumeni syndrome) and the myotonic dystrophies (DM), by classic and molecular genetics and genomics approaches.
Li-Fraumeni syndrome (LFS) is a genetically heterogeneous, rare inherited cancer syndrome. Most cases are due to mutations in the tumor suppressor p53. We have mapped another LFS locus to 1q23, which we are positionally cloning. In p53 and non-p53 LFS, there is evidence for risk modifiers and factors in addition to the inherited susceptibility. We are using integrated approaches combining genomic and epigenomic profiling to dissect the complex genetic and epigenetic events underlying LFS tumorigenesis. To dissect the pathophysiological consequences of variant genes, we are generating suitable LFS mouse models. LFS predisposition and/or modifier genes may also be functionally important in other tumor types lacking a clear genetic predisposition. The molecular characterization and classification of sporadic cancers (head and neck and lung cancer, and gliomas) through genomics methodologies to identify genomic, epigenomic and transcriptomic changes underlying tumor initiation, progression and metastasis is another focus.
Myotonic dystrophy, the most common adult neuromuscular disorder, is caused by mutant (CTG)DM1 or (CCTG)DM2 expansions that when transcribed cause disease. It is unclear how these mutant (CUG)DM1/(CCUG)DM2 RNAs mediate their disease-causing effects at the molecular and cellular level. To dissect the pathophysiology, we are using functional genomics and molecular genetics approaches and have generated transgenic, knock-in and knock-out mouse models.
Aminoff M, Carter JE, Chadwick RC, Johnson C, Gräsbeck R, Abdelaal MA, Broch H, Jenner LB, Verroust P, Moestrup SK, de la Chapelle A, Krahe R (1999) Mutations in CUBN, encoding the intrinsic-factor-vitamin B12 receptor, cause hereditary megaloblastic anemia 1. Nature Genet 21: 309-313.
Virtaneva K, Wright FA, Tanner SM, Yuan B, Lemon WJ, Caligiuri MA, Bloomfield CD, de la Chapelle A, Krahe R (2001) Gene expression profiling reveals fundamental biological differences in AML with trisomy 8 and normal cytogenetics. Proc Natl Acad Sci USA 98: 1124-1129.
Bachinski LL, et al., and Krahe R (2003) Confirmation of the type 2 myotonic dystrophy (CCTG)n expansion mutation in patients with proximal myotonic myopathy/proximal myotonic dystrophy of different European origins: a single shared haplotype indicates an ancestral founder effect. Am J Hum Genet 73, 835-848.
Cheung HC, Baggerly KA, Tsavachidis S, Bachinski LL, Neubauer VL, Nixon TJ, Aldape KD, Cote GJ, Krahe R (2008) Global exon analysis reveals that aberrant RNA splicing in glioblastoma is rare. BMC Genomics 12: 216.