MLH1 and Leigh syndrome: Although growing evidence reveals that germline variations in MLH1 and MSH2 genes are likely responsible for around 60%–70% of LS,13 we have found three probands (As/1, Bg/9, Hm/25) without variants in either MLH1 or MSH2 genes and the primary tumors found on these three unique cases were interestingly left‐sided (Table 2).