Genetic variation, expression and ontogeny of sulfotransferase SULT2A1 in humans

Sulfotransferases (SULTs) are enzymes involved in the metabolism of several endogenous molecules. The activity and expression exhibit inter- and intra-individual variations due to age and genetic variation. The aims of this study were to compare the gene expression of SULT2A1 in fetal and adult livers, to study the intra-individual tissue distribution, and investigate if expression is associated with a SULT2A1 copy number variation polymorphism. In contrast to other drug metabolizing enzyme systems the expression of SULT2A1 did not differ between fetal and adult liver samples and it was not affected by maternal smoking or gestational age. Gene expression in relation to sex could not be assessed as the sex of the fetuses was unknown. SULT2A1 was consistently expressed in livers and adrenals, being seven times more abundant in adrenals, but was absent in the lungs. The SULT2A1 copy number variation was proportional to gene expression in liver and adrenals. Our results show that SULT2A1 is important in the first trimester; particularly in the adrenals.