DYRK1A and microcephaly: Of note, DYRK1A haploinsufficiency in D-CRO1-Δ1 and D-CRO1-Δ5 organoids did result in these two lines producing smaller organoids than T-CRO1 (Fig. 9d), underpinning the clinical reports of DYRK1A haploinsufficiency causing microcephaly.64