Codon Exon Substitution n Codon Exon Substitution n M918 16 T 361 P766 13 S 1 C634 11 W/S/T/Y/A/F/C 42 V778 13 V 1 A883 15 T/F/S/P 18 Q781 13 R 1 C630 11 S/G/R/A 15 V804 14 M 1 C618 10 R/Y/S 7 K808 14 E 1 C620 10 W/R/S 5 K821 14 E 1 E768 13 D 4 A876 15 V 1 C611 10 R 2 E884 15 K 1 D631 11 N/G 2 G894 15 S 1 A513 8 G 1 E901 15 K 1 Q681 11 ? 1 R908 15 K 1 V691 11 I 1 A919 16 V 1 E615 10 K 1 E921 16 K 1 V648 11 I 1 S922 16 P 1 V706 11 A 1 S922 16 I 1 G748 13 C 1 T930 16 M 1

Table 2: Somatic RET point mutations in sporadic MTC, data derived from “COSMIC, catalogue of somatic mutation in cancer” http://cancer.sanger.ac.uk/cancergenome/projects/cosmic/