Both Nedd4-1 and Nedd4-2 (a close relative) have been proposed to play a role in Liddle's syndrome (a rare hereditary form of hypertension), the budding of retroviruses including HIV-1 and HTLV-1 (which are etiologically associated with AIDS and adult T-cell leukemia, respectively) and T-cell receptor (TCR) signaling [45-47]. This evidence concerns the gene NEDD4L and Liddle syndrome.