Hot water epilepsy is a reflex or sensory epilepsy in which seizures are 
triggered by the stimulus of bathing in hot water. Although there is evidence of 
a genetic basis to its etiology, no gene associated with this disorder has so 
far been found. In order to identify the genetic locus involved in the 
pathophysiology of hot water epilepsy, we performed a genome-wide linkage 
analysis in a four-generation family manifesting the disorder in an autosomal 
dominant manner. Significant linkage was detected on chromosome 4q24-q28, with 
the highest two-point LOD score of 3.50 at recombination value (theta) of 0 for 
the marker D4S402. Centromere-proximal and centromere-distal boundaries of this 
locus were defined by the markers D4S1572 and D4S2277, respectively. The 
critical genetic interval spans 22.5 cM and corresponds to about 24 megabases of 
DNA. The genes NEUROG2, ANK2, UGT8 and CAMK2D, which are known to be expressed 
in human brain, are strong positional candidates and we propose to examine these 
and other genes in the locus to identify the causative gene for this intriguing 
form of epilepsy.