Wolcott-Rallison Syndrome (WRS), also known as Multiple Epiphyseal Dysplasia with Early-onset Diabetes Mellitus is a rare autosomal recessive multisystemic disorder. Its characteristic clinical features are permanent neonatal or early infancy insulin-dependent diabetes and later onset skeletal dysplasia. Other frequent clinical manifestations are hepatic and renal dysfunction, mental retardation, cardiac abnormalities, exocrine pancreatic dysfunction, primary hypothyroidism and neutropenia. This report presents an 8-year-old WRS case who is found to have W522X mutation in EIF2AK3 gene which was only found in two other unrelated Turkish families. W522X mutation in EIF2AK3 gene seems to be confined to Turkey and may be a common mutation in WRS patients from this country. In this paper, we evaluate the clinical features of the patients having W522X mutation and we compare this group with other patients reported to date. Except the characteristic features as diabetes mellitus and epiphyseal dysplasia, all the WRS patients, including patients with W522X mutation, show extensive phenotypic variability that correlates poorly to genotype which suggests that there is no correlation between a specific mutation and the clinical manifestation.