Lynch syndrome is the most common type of hereditary cancer syndrome, affecting 1 in 280–400 individuals. This predisposition to cancer is caused by inherited or germline pathogenic changes in the DNA mismatch repair (MMR) genes MLH1, MSH2, MSH6, and PMS2. In some cases, constitutional promoter methylation of MLH1 or MSH2 (secondary to an EPCAM5′ deletion) is also identified.
Conclusion: it may be appropriate to consider categorising Lynch syndrome as 4 distinct syndromes based on the specific altered MMR gene.
The varying carcinogenic mechanisms and associated cancer risks indicate the need for gene-specific surveillance recommendations in Lynch syndrome. Moreover, the growing understanding of gene-specific differences will likely affect treatment options and efficacy of Lynch syndrome vaccines.
https://www.gastrojournal.org/article/S0016-5085(23)00696-0/fulltext
Lynch Syndrome Ireland 