TBL1XR1 and Pierpont syndrome: In contrast to the prior literature linking Pierpont Syndrome to a small number of specific missense variants in TBL1XR1 [8, 10, 15, 36], individuals in this survey received the diagnosis associated with a wide array of genetic variants in TBL1XR1, including other missense variants, premature truncation, and CNV (Fig. 1b).