Disruption of sodium bicarbonate transporter SLC4A10 in a patient with complex partial epilepsy and mental retardation.

OBJECTIVE To determine gene(s) disrupted in a patient with partial frontal lobe epilepsy and cognitive impairment with concomitant de novo balanced chromosomal translocation t(2;13)(q24;q31). DESIGN Fluorescence in situ hybridization and array comparative genomic hybridization were used to map the locations of chromosomal translocation breakpoints. RESULTS SLC4A10 (OMIM 605556), a sodium bicarbonate transporter gene with high expression in the cerebral cortex and hippocampus, was disrupted by the translocation breakpoint on chromosome 2q24. The breakpoint on chromosome 13q31 was in a 1-megabase (Mb)-gene desert. Genomewide array comparative genomic hybridization confirmed the absence of additional chromosomal abnormalities. CONCLUSION SLC4A10 is the third SLC4 base transporter family member to be implicated in human cognition and epilepsy.