TSHR and hydatidiform mole: It has been also suggested that basic isoforms with lower sialic acid content have greater efficiency in activating the TSH-R and its cAMP-pathways, as well as a high bioactivity/immunoactivity ratio in CHO cells expressing human TSH-R; mostly basic isoforms of hCG with more thyrotropic activity were revealed in cases with hydatidiform moles.