The gene encoding ChREBP has had multiple names, initially named WBSCR14 as it was found in a deletion associated with Williams-Beuren syndrome [16,17], with its current gene name being MLXIPL. Transcriptional activation of gene expression by ChREBP requires the formation of a heterodimer with a second basic helix-loop-helix protein, the 244-amino-acid-long protein MLX (Max dimerization protein, also known as Max-like protein X and TCFL4, transcription factor-like 4, encoded by MLX) [18,19]. The gene discussed is MLXIPL; the disease is Williams syndrome.