BUB1B and microcephaly: Previous work in mice found that a BubR1 hypomorphic allele substantially reduces protein level presenting with premature aging, and tumor formation, but not microcephaly (Baker et al., 2004; Hanks et al., 2004; Matsuura et al., 2006; Frio et al., 2010; Suijkerbuijk et al., 2010; Miyamoto et al., 2011; Baker et al., 2012; Wijshake et al., 2012; Choi et al., 2016; Yang et al., 2017; Pavone et al., 2022).