To date, 3 heterozygous disease-causing SGMS2 variants have been identified: c148C>T (p.Arg50*) leading to early-onset osteoporosis, c.185T>G (p.Ile62Ser) and c.191T>G (p.Met64Arg) leading to a more severe spondylometaphyseal dysplasia.2 Here, SGMS2 is linked to spondylometaphyseal dysplasia.