FLNB and Larsen syndrome: As well as classic Larsen syndrome, individuals heterozygous for FLNB mutations can also have a number of lethal osteochondrodysplasia phenotypes such as atelosteogenesis type I (AOI; MIM# 108720) and type III (AOIII; MIM# 108721) and the especially severe boomerang dysplasia (MIM# 112310) (Bicknell et al., 2005; Farrington‐Rock et al., 2006).