ABCMdb

PMID: 25071991

Chen N, Prada AE
Development of allele-specific multiplex PCR to determine the length of poly-T in intron 8 of CFTR.
PeerJ. 2014 Jul 8;2:e468. doi: 10.7717/peerj.468. eCollection 2014., [PubMed]

Sentences

No. Mutations Sentence Comment

1 ABCC7 p.Arg117His Although poly-T allele analysis in intron 8 of CFTR is required when a patient is positive for R117H, it is not recommended for routine carrier screening. Login to comment 2 ABCC7 p.Arg117His Therefore, commercial kits for CFTR mutation analysis were designed either to mask the poly-T allele results, unless a patient is R117H positive, or to have the poly-T analysis as a standalone reflex test using the same commercial platform. Login to comment 21 ABCC7 p.Arg117His Additional testing of the poly-Thymidine (poly-T) tract in intron 8 of CFTR is indicated when a patient is positive for R117H, one of the 23 recommended mutations (Grody et al., 2001). Login to comment 25 ABCC7 p.Arg117His ABCC7 p.Arg117His Presence of both R117H and 5T allele on the same chromosome (i.e., R117H and 5T in cis-configuration) constitutes a disease-causing CF mutation (Bienvenu et al., 1993; Chmiel et al., 1999; Dean et al., 1990). Login to comment 27 ABCC7 p.Arg117His ABCC7 p.Arg117His Testing parents of patients is able to define whether R117H and 5T are from the one parent (i.e., in cis-configuration) or different parent (i.e., in trans-configuration), if 5T is detected in R117H positive samples. Login to comment 28 ABCC7 p.Arg117His ABCC7 p.Arg117His Because R117H and poly-T alleles are about 18 kb apart, long-range PCR has also been developed to determine the cis- or trans-relationship of R117H and 5T alleles to circumvent testing unaffected parents (Chen & Schrijver, 2011; Pont-Kingdon et al., 2004). Login to comment 30 ABCC7 p.Arg117His For this reason, some commercial assays mask the results of the poly-T tract and only provide poly-T results when the samples are R117H positive. Login to comment 32 ABCC7 p.Arg117His When a clinician wants to test the poly-T tract for a male patient with clinical indication of CBAVD, a standalone poly-T test (i.e., poly-T test in a separate tube) would be ordered, because it is impossible to obtain the poly-T tract results with R117H negative samples if laboratories only run commercial CFTR mutation analysis with masked poly-T results. Login to comment 208 ABCC7 p.Arg117His Overall, we developed a simple, easy to implement standalone multiplex AS-PCR method to detect all three poly-T alleles in intron 8 of CFTR. Our assay can be implemented as a reflex test in patients with positive R117H, if another method for CFTR mutation analysis didn`t include poly-T analysis. Login to comment