Inversion of exons 1–7 (8) of the MSH2 gene is a frequent cause of unexplained Lynch syndrome in one local population

open access (technical)

Fig. 3

Pedigrees of patients who are carriers of the MSH2 gene inversion. Cancer history is illustrated as reported by the probands. Only Lynch syndrome-related cancers are shown. Inconsistencies in cancer incidence and ages of onset were found when comparing ...

Table 1

Clinical characteristics of unexplained MSH2-type Lynch syndrome patients

 In our analysis, we used allelic drop out in long PCR analysis as a method to find regions of possible inversions. This method could be further developed to look for other inversion in the MSH2 gene, as well as in other genes where current methods of testing fail to find a causative mutation. In the meantime, clinical testing services should add an analysis for the 10 Mb inversion to their clinical testing repertoire. This study also demonstrates the importance of enrolling patients with suspected Lynch syndrome, but negative germline testing results, into research registries where their DNA can be tested until an answer is found.