Figure 1 Molecular results. The family reference number is labelled to allow correlation with the tables. There were 22 different mutations within the PTEN gene, in addition to an entire exon 1 deletion in a patient who met the CS criteria. Mutations were not clustered in any one part of the gene. Three mutations were in the PTPase core motif in exon 5, but no point mutations were identified in the first or third exons. There are 15 previously unreported mutations, including one in exon 9. Where proven, 9 of the mutations were de novo, 7 mutations were paternally inherited and 3 were maternally inherited.