HomeResearchIntramural ResearchResearch Branches at NHGRIGenetics and Molecular Biology Branch Sood Lab

Raman Sood, Ph.D. Associate Investigator Genetics and Molecular Biology Branch M.Sc. Guru Nanak Dev University, India, 1984 Ph.D. Queen's University, Kingston, Canada, 1989 (301) 435-5746 (301) 402-4929 rsood@nhgri.nih.gov Building 49, Room 3A30 49 Convent Dr, MSC 4442 Bethesda, MD 20892-4442 Selected Publications

Dr. Sood's research is focused on generating a resource for National Human Genome Research Institute investigators that will allow them to perform functional analyses of genes of interest using zebrafish as a model organism. This work is performed within the Oncogenesis and Development Section, led by Dr. Paul Liu.

Currently, Dr. Sood is performing large-scale N-ethyl-N-nitrosourea (ENU) mutagenesis in zebrafish, which produces random point mutations throughout the organism's genome. Her goal is to develop approximately 5,000 F1 male fish bearing such mutations, a number that makes it highly likely that there will be an individual in the collection carrying a mutation in every gene that researchers may wish to study. Dr. Sood uses reverse genetic approaches to identify mutants for genes of interest. Her major focus is to identify mutations in genes involved in hematopoiesis and cancer and to study their phenotype to understand the function of these genes. She does this by generating lines of zebrafish for mutations of functional significance and breeds them to homozygosity to study the phenotype.

To identify potentially interesting mutations in the collection of ENU-treated zebrafish, Dr. Sood is employing sequencing in combination with TILLING (for "targeting induced local lesions in genomes"), which provides a cost-effective alternative to sequencing large numbers of samples. In high-throughput TILLING, regions of interest are amplified by polymerase chain reaction (PCR). Heteroduplexes between wild-type fragments and fragments harboring an induced mutation are formed by denaturing and reannealing PCR products. These heteroduplexes are cleaved by an endonuclease, CEL I. Cleaved products are then resolved using denaturing polyacrylamide gel or capillary electrophoresis. To increase throughput, samples are pooled fourfold. Upon detection of a mutation in a pool, the individual DNA samples are sequenced to identify the individual carrying the mutation and the nature of the mutation. This rapid screening procedure determines the location of a mutation to within about 10 bp for PCR products that are 300 bp to 600 bp in size.

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Last Reviewed: August 21, 2008