EXOC6B and X-linked spondyloepimetaphyseal dysplasia: Pathogenic variants in EXOC6B (Sec15B) have been identified in six patients with spondylo-epi-metaphyseal dysplasias with joint laxity (SEMDJL) (Girisha et al. 2016; Campos-Xavier et al. 2018; Simsek-Kiper et al. 2022) (Table 1), a skeletal disorder characterized by spine deformities, severe joint laxity, and multiple joint dislocations.