GFI1 and Down syndrome: In addition, mutations at a number of rarely affected genes, among them e.g., G6PC3 (glucose 6 phosphatase, catalytic, 3) (6), GFI1 (growth factor independent 1) (7), TAZ (tafazzin) (8), WAS (Wiskott-Aldrich syndrome) (9) and JAGN1 (Jagunal Homolog 1) (10) have been identified in CN (11).