The primary objective of this research proposal is mapping and characterization of genes that contribute to epilepsy. This is achieved by studying epileptic individuals who have balanced chromosomal rearrangement with a breakpoint in a locus implicated in epilepsy. Three such cases, DGAP095, 097 and 131 (dgap.harvard.edu), are being investigated in this proposal. Analysis of breakpoints in DGAP095 showed that the DGKD gene is disrupted by rearrangement at the 2q37 locus, which maps near one of the seizure susceptibility loci in humans. We propose that DGKD disruption is pathogenetic to the seizure phenotype exhibited by the patient in light of the (1) implication of diacylglycerol kinases in neural signaling, (2) murine DGKD localization near a seizure susceptibility locus, and (3) DGKD expression in developing CNS in model organisms. DGKD ortholog expression will be assessed in various sections of the mouse brain, and studies confirming the etiologic role of DGKD will include construction of a mouse model. In DGAP097 and 131, breakpoints Xp22.1 and 5q13 lie near epilepsy implicated loci. They will be positioned on the human genome map using fluorescence in situ hybridization and the sequence at the breakpoints will be analyzed in a search for potential candidate genes, if the breakpoint falls within a gene-coding region, Northern blot analyses will be used to assess the presence or absence of novel transcript(s) due to the rearrangement. A prospective mutation scan in families with epilepsy /inked to the locus of interest as well as in patients with epilepsy inherited in an autosomal dominant fashion is a future direction of this research, and could be done using single-stranded conformation polymorphism or denaturing gradient gel electrophoresis with subsequent sequencing of aberrant PCR fragments.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
1F32HD043627-01A2
Application #
6792838
Study Section
Special Emphasis Panel (ZRG1-F08 (20))
Program Officer
Moody, Sally Ann
Project Start
2004-07-08
Project End
2007-07-07
Budget Start
2004-07-08
Budget End
2005-07-07
Support Year
1
Fiscal Year
2004
Total Cost
$47,296
Indirect Cost
Name
Brigham and Women's Hospital
Department
Type
DUNS #
030811269
City
Boston
State
MA
Country
United States
Zip Code
02115
Higgins, Anne W; Alkuraya, Fowzan S; Bosco, Amy F et al. (2008) Characterization of apparently balanced chromosomal rearrangements from the developmental genome anatomy project. Am J Hum Genet 82:712-22
Leach, Natalia T; Sun, Yi; Michaud, Sebastien et al. (2007) Disruption of diacylglycerol kinase delta (DGKD) associated with seizures in humans and mice. Am J Hum Genet 80:792-9