 Studies showed that mutations in "CUBN" or "AMN" clustered particularly in the Scandinavian countries and the Eastern Mediterranean regions.Founder effect, higher clinical awareness to IGS, and frequent consanguineous marriages all play a role in the higher prevalence of IGS among these populations.The syndrome is the result of the collective work done by a Norwegian pediatrician, Olga Imerslund, a Finnish physician and clinical biochemist, Armas Ralph Gustaf Gräsbeck, and Emil Najman, a pediatrician from Croatia.