FBN1 and geleophysic dysplasia: Interestingly, studies have shown that missense mutations in exon 41 or 42 of FBN1 cause geleophysic dysplasia (GD, MIM #614185) or acromicric dysplasia (AD, MIM #102370) through a gain-of-function mechanism, which is characterized by severe short stature, short hands and feet, joint stiffness, and skin thickening, but without cardiac involvement or early death (Le Goff et al., 2011; Passarge et al., 2016).