Notably, mutations of Rnu12 detected in monocytes lead to early onset of cerebellar ataxia, a neurodegenerative disease that is known to correlate with sleep disruption (Velázquez-Pérez et al. 2011; Elsaid et al. 2017; Werdann and Zhang 2020). Here, RNU1-2 is linked to aceruloplasminemia.