To the best of our knowledge, only a few groups of reports hypothesised the possibility of a founder GCK mutation [13,14,15] or the description of a small group of MODY patients carrying the same mutations originating from the same geographic region: in European MODY populations, five unrelated families from Oxford with p.Gly299Arg [16] and three different mutations in Spain (p.Val182Leu in three families from Cantabria, p.Glu399X in two families from Albacete, and p.Ala379Val in two families from Basquete) [17] were found. This evidence concerns the gene GCK and MODY.