Molecular characterization of lynch syndrome in Tunisia

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Published Jan 27, 2015
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Vol. 92 No. 7 (2014): Issue Jul 2014

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Sana Aissi
Farid Zérimech
Amel Moussa
Nadia Kourda
Amel Mezlini
Nabil Abdelli
Taoufik Najjar
Farhat Ben Ayed
Sarah Ben Jilan
Mohamed Manai
Marie-Pierre Buisine

Abstract

Background: High rates of early colorectal cancers (CRC) are observed in Tunisia suggesting genetic susceptibility. Nevertheless, up to now no molecular studies have been performed in the Tunisian population.


Aim: To evaluate the clinical and genetic characteristics of Tunisian families suspected of hereditary nonpolyposis colorectal cancer (HNPCC) and to identify new tumoral markers for CRC susceptibility leading to distinguish patients with sporadic CRC from those with familial CRC, like HNPCC. Methods: 31 unrelated families suspected of HNPCC were screened for germline mutations in MMR genes. We have also analyzed tumoral phenotype and the genetic characteristics of tumors from 51 patients with CRC meeting the Bethesda criteria.

Results: 10 different germ line mutations, 8 of which were novel, were identified in 11 out of the 31 families (35.5%), 5 in MSH2 and 5 in MLH1. Our results showed that MUC5AC expression was more frequent in patients with family history of CRC (p=0.039). Conclusion: The analysis of MUC5AC expression might be very beneficial in the detection of Tunisian patients with high susceptibility to CRC.

Keywords:

HNPCC, MMR, MLH1, MSH2, MSI, MLPA, MUC5AC.

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