EVIDENCE FOR X-LINKAGE OF STEROID SULFATASE IN THE MOUSE: STEROID SULFATASE LEVELS IN OOCYTES OF XX AND XO MICE

Stanley M. Gartler ¹ and Martha Rivest ¹

¹ Department of Medicine, Department of Genetics, and the Center for Inherited Diseases, University of Washington, Seattle, Washington 98195

The steroid sulfatase (STS) levels in mature oocytes of XX and XO mice were assayed along with lactate dehydrogenase (LDH), an autosomal marker, and glucose-6-phosphate dehydrogenase (G6PD), a known X-linked gene. LDH levels in XX and XO oocytes were equal, whereas STS and G6PD levels were approximately twice as high in XX oocytes as in XO oocytes. These results indicate that the STS gene is X-linked in the mouse just as it is in humans. Assays of STS in kidney tissue of XX and XO mice indicated dosage compensation for the gene, which is different from that observed in humans.