STX3 and microvillus inclusion disease: In 90% of cases, MVID is caused by gene variants of Myosin Vb (MYO5B), with variants of syntaxin-3 (STX3) and its binding partner syntaxin binding protein 2 (STXBP2) are responsible for the remaining 10% of cases (Müller et al., 2008; Vogel et al., 2017; Wiegerinck et al., 2014).