PTPN11 and Noonan syndrome: For example, Tartaglia and colleagues assessed PTPN11 (SHP2) mutations by comparing somatic mutations in juvenile myelomonocytic leukaemia (JMML) with Noonan syndrome germline mutations, and they identified a greater activation of the RAS/MAPK activation for the JMML‐associated mutations (Tartaglia et al, 2003).