domingo, 4 de marzo de 2018

N_LyST: a simple and rapid screening test for Lynch syndrome. - PubMed - NCBI

2018 Feb 22. pii: jclinpath-2018-205013. doi: 10.1136/jclinpath-2018-205013. [Epub ahead of print]

N_LyST: a simple and rapid screening test for Lynch syndrome.

Susanti S1,2,3, Fadhil W1,3, Ebili HO1,3,4, Asiri A1,3, Nestarenkaite A5, Hadjimichael E1,3, Ham-Karim HA1,3, Field J6, Stafford K6, Matharoo-Ball B7, Hassall JC1,3, Sharif A6, Oniscu A8, Ilyas M1,3.

Author information

Abstract

AIMS:

We sought to use PCR followed by high-resolution melting analysis to develop a single closed-tube screening panel to screen for Lynch syndrome. This comprises tests for microsatellite instability (MSI), MLH1 methylation promoter and BRAF mutation.

METHODS:

For MSI testing, five mononucleotide markers (BAT25, BAT26, BCAT25, MYB, EWSR1) were developed. In addition, primers were designed to interrogate Region C of the MLH1 promoter for methylation (using bisulphite-modified DNA) and to test for mutations in codon 600 of BRAF. Two separate cohorts from Nottingham (n=99, 46 with MSI, 53 being microsatellite stable (MSS)) and Edinburgh (n=88, 45 MSI, 43 MSS) were tested.

RESULTS:

All the cases (n=187) were blind tested for MSI and all were correctly characterised by our panel. The MLH1 promoter and BRAFwere tested only in the Nottingham cohort. Successful blinded analysis was performed on the MLH1 promoter in 97 cases. All MSS cases showed a pattern of non-methylation while 41/44 cases with MSI showed full methylation. The three cases with MSI and a non-methylated pattern had aberrations in MSH2 and MSH6 expression. BRAF mutation was detected in 61% of MSI cases and 11% of MSS cases.Finally, 12 cases were blind screened by using the whole panel as a single test. Of these, five were identified as MSS, four as MSI/non-LS and three as MSI/possible LS. These results were concordant with the previous data.