Mutation analysis of the multidrug resistance protein 2 (MRP2) gene in a Japanese patient with Dubin-Johnson syndrome.

Dubin-Johnson syndrome (DJS) is a recessive inherited disorder with conjugated hyperbilirubinemia caused by a dysfunction of multidrug resistance protein 2 (MRP2) on the canalicular membrane of hepatocytes. A mutational analysis of the MRP2 gene was carried out in a Japanese female with DJS. In this patient, we found a homozygous 2125T > C mutation in exon 17. This mutation affects the conversion of tryptophan(709) to arginine(709) (W709R) in the first ATP-binding cassette in the MRP2 protein. It was concluded that this homozygous mutation of the MRP2 gene contributed to the induction of hyperbilirubinemia in this case.