In addition, limited data were found regarding molecular testing, with 7% of participants only having had IHC testing for MMR proteins MLH1/ MSH2 / MSH6/ PMS2, which is necessary for the diagnosis for LS. Four of the participants (57%) had loss of at least one expression of MMR proteins, and three of them were younger than 50 years old, and only one reported family history of EC. Here, PMS2 is linked to Leigh syndrome.