KIF22 and spondyloepimetaphyseal dysplasia, matrilin-3 type: ,262 Note that KIF22-associated spondyloepimetaphyseal dysplasia with joint laxity type 2 is also characterized by spinal deformities,226 so that additive or epistatic interactions between 16p11.2 genes could contribute to heterogeneity in skeletal phenotypes.