The function of HS2ST1 (heparan sulfate 2-O-sulfotransferase 1, Ensembl gene identifier ENSG00000153936) is as follows. Catalyzes the transfer of a sulfo group from 3'-phospho-5'- adenylyl sulfate (PAPS) to the 2-OH position of iduronic acid (IdoA) or glucuronic acid (GlcA) within the heparan sulfate (HS) chain and participates in HS biosynthesis (By similarity). Required for metanephric development of kidney formation, suggesting that 2-O- sulfation within HS is essential for signaling between ureteric bud and metanephric mesenchyme (By similarity). {ECO:0000250|UniProtKB:Q76KB1, ECO:0000250|UniProtKB:Q8R3H7}.