ABCMdb

ABCC7 p.Leu927Pro

Admin's notes:	Class II-III (maturation defect, gating defect) Veit et al.
ClinVar:	c.2780T>C , p.Leu927Pro D , Pathogenic
CF databases:	c.2780T>C , p.Leu927Pro D , CF-causing ; CFTR1: A new mutation in exon 15 was identified in exon 15 in three Dutch Cf patients (out of 148 non [delta[F508 chromosomes). This mutation was detected by direct sequence analysis of exon 15 in one CF patient and is a base pair substitution (T at position 2912 to a C) resulting in a replacement of a leucine by a proline at position 927. Two of the CF patients have the [delta]F508 mutation on the other allel, wheras the third one has the [delta]L1260 mutation as second mutation.
Predicted by SNAP2:	A: N (61%), C: N (72%), D: D (80%), E: D (75%), F: N (78%), G: D (66%), H: D (75%), I: N (87%), K: D (75%), M: N (57%), N: D (63%), P: D (80%), Q: D (59%), R: D (75%), S: D (63%), T: D (59%), V: N (93%), W: D (59%), Y: D (71%),
Predicted by PROVEAN:	A: N, C: N, D: D, E: D, F: N, G: D, H: D, I: N, K: D, M: N, N: D, P: D, Q: D, R: D, S: N, T: N, V: N, W: D, Y: N,

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II-III (maturation defect, gating defect) <a href="https://www.ncbi.nlm.nih.gov/pubmed/26823392">Veit et al.</a>
admin on 2016-08-19 15:16:22

Publications
[hide] Pharmacological induction of CFTR function in pati... Pediatr Pulmonol. 2005 Sep;40(3):183-96. Kerem E
Pharmacological induction of CFTR function in patients with cystic fibrosis: mutation-specific therapy.
Pediatr Pulmonol. 2005 Sep;40(3):183-96., [PMID:15880796]

Abstract [show]
CFTR mutations cause defects of CFTR protein production and function by different molecular mechanisms. Mutations can be classified according to the mechanisms by which they disrupt CFTR function. This understanding of the different molecular mechanisms of CFTR dysfunction provides the scientific basis for the development of targeted drugs for mutation-specific therapy of cystic fibrosis (CF). Class I mutations are nonsense mutations that result in the presence of a premature stop codon that leads to the production of unstable mRNA, or the release from the ribosome of a short, truncated protein that is not functional. Aminoglycoside antibiotics can suppress premature termination codons by disrupting translational fidelity and allowing the incorporation of an amino acid, thus permitting translation to continue to the normal termination of the transcript. Class II mutations cause impairment of CFTR processing and folding in the Golgi. As a result, the mutant CFTR is retained in the endoplasmic reticulum (ER) and eventually targeted for degradation by the quality control mechanisms. Chemical and molecular chaperones such as sodium-4-phenylbutyrate can stabilize protein structure, and allow it to escape from degradation in the ER and be transported to the cell membrane. Class III mutations disrupt the function of the regulatory domain. CFTR is resistant to phosphorylation or adenosine tri-phosphate (ATP) binding. CFTR activators such as alkylxanthines (CPX) and the flavonoid genistein can overcome affected ATP binding through direct binding to a nucleotide binding fold. In patients carrying class IV mutations, phosphorylation of CFTR results in reduced chloride transport. Increases in the overall cell surface content of these mutants might overcome the relative reduction in conductance. Alternatively, restoring native chloride pore characteristics pharmacologically might be effective. Activators of CFTR at the plasma membrane may function by promoting CFTR phosphorylation, by blocking CFTR dephosphorylation, by interacting directly with CFTR, and/or by modulation of CFTR protein-protein interactions. Class V mutations affect the splicing machinery and generate both aberrantly and correctly spliced transcripts, the levels of which vary among different patients and among different organs of the same patient. Splicing factors that promote exon inclusion or factors that promote exon skipping can promote increases of correctly spliced transcripts, depending on the molecular defect. Inconsistent results were reported regarding the required level of corrected or mutated CFTR that had to be reached in order to achieve normal function.

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58 C-D565G II DF508 D1507 S549R S549I S549N S549R S945D S945L H1054D G1061R L1065P R1066C R1066M L1077P H1085R N1303K G85E III G551D S492F V520F R553G R560T R560S Y569D IV R117H, R117C, R117P, R117L D1152H, L88S, G91R, E92K, Q98R, P205S, L206W, L227R, F311L, G314E, R334W, R334Q, I336K, T338I, L346P, R347C, R347H, R347L, R347P, L927P, R1070W, R1070Q V 3849 þ 10 kb C ! Login to comment

[hide] Serum zinc concentrations in cystic fibrosis patie... Biol Trace Elem Res. 2007 Oct;119(1):19-26. Van Biervliet S, Van Biervliet JP, Vande Velde S, Robberecht E
Serum zinc concentrations in cystic fibrosis patients aged above 4 years: a cross-sectional evaluation.
Biol Trace Elem Res. 2007 Oct;119(1):19-26., [PMID:17914215]

Abstract [show]
AIM: Assess the risk of zinc (Zn) deficiency in the older cystic fibrosis (CF) population. METHOD: Cross-sectional investigation of all CF patients above the age of 4 followed at the Ghent University center between 2002 and 2003. Data on age, weight, height z-score, pancreatic and pulmonary functions, chronic Pseudomonas infection, and CF transmembrane conductance regulator (CFTR) mutations were collected. Serum Zn, vitamins (vit) A and E, retinol-binding protein (RBP), albumin, sedimentation rate, total IgG, and cholesterol were determined. Serum Zn was compared with a local healthy control group (Van Biervliet et al., Biol Trace Elem Res 94:33-40, 2003) and with literature data (Hotz C, et al. Am J Clin Nutr 78:756-764, 2003). RESULTS: 101 patients (median age 16 years) were included. There was no difference in serum Zn concentration between CF patients and controls. In CF patients no difference in serum Zn concentration between pancreatic-sufficient or pancreatic-insufficient patients was seen. Serum Zn was not associated to nutritional status or height z-score. A significant association serum Zn to serum albumin (p < 0.0005) and to vit A (p < 0.01) was seen. No associations of serum Zn to serum vit E, RBP, cholesterol, or CFTR were present, but there is a significant association serum Zn to forced vital capacity (p < 0.01). Serum Zn was not associated to inflammatory parameters or chronic Pseudomonas infection. CONCLUSION: Comparison of CF patients with local controls revealed no significant differences. However, because persisting steatorrhea increases Zn loss (Easley et al., J Pediatr Gastroenterol Nutr 26:136-139, 1998) and 12.6% of our population has a serum Zn below the p value of 2.5 of the NHANES II study (Hotz C, et al. Am J Clin Nutr 78:756-764, 2003), there could remain an increased risk of Zn deficiency in some CF patients. Furthermore, the association with pulmonary function needs more investigation.

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73 Table 1 Genotype of the 101 CF Patients: Details of the CF Mutations and Classification into Two Groups Genotype Groups Genotype No of Patients A ΔF508/ΔF508 47 ΔF508/E60X 1 ΔF508/G542X 7 ΔF508/N1303K 3 ΔF508/Q493X 1 ΔF508/1717-1G→A 1 ΔF508/Y1092X 1 ΔF508/394delTT 1 ΔF508/R785X 1 ΔF508/R553X 1 ΔF508/ΔI507 1 394delTT/394delTT 1 N1303K/N1303K 2 B ΔF508/3849+10kbC-T 1 ΔF508/306ΔTAGA 1 ΔF508/S1251N 8 ΔF508/L927P 1 G458V/1717-1G→A 1 ΔF508/I336K 2 G542X/622-2 A→C 1 ΔF508/G970R 3 ΔF508/3272-26A→G 2 ΔF508/R117H 2 ΔF508/2789+5G→A 2 1717-1G->A/S1251N 1 G542X/G970R 1 394delTT/Y913C 1 N1303K/deletion exon 19 1 Unidentified/unidentified 2 3600+2insTA/2005 del T 1 ΔF508/1898+1G→A 1 Deletion exon 2/del exon 2 1 There was no difference according to gender or age. Login to comment

[hide] High incidence of the CFTR mutations 3272-26A-->G ... J Cyst Fibros. 2007 Nov 30;6(6):371-5. Epub 2007 May 3. Storm K, Moens E, Vits L, De Vlieger H, Delaere G, D'Hollander M, Wuyts W, Biervliet M, Van Schil L, Desager K, Nothen MM
High incidence of the CFTR mutations 3272-26A-->G and L927P in Belgian cystic fibrosis patients, and identification of three new CFTR mutations (186-2A-->G, E588V, and 1671insTATCA).
J Cyst Fibros. 2007 Nov 30;6(6):371-5. Epub 2007 May 3., [PMID:17481968]

Abstract [show]
We have analyzed 143 unrelated Belgian patients with a positive diagnosis of cystic fibrosis (CF) for mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. An initial screening for 29 CFTR mutations led to mutation identification in 89.9% of the tested chromosomes. Subsequently an extensive analysis of the CFTR gene was performed by denaturating gradient gel electrophoresis (DGGE) in those patients with at least one unknown mutation after preliminary screening. In addition to 10 previously reported mutations we identified 2 new mutations 186-2A-->G and E588V. A third new mutation 1671insTATCA was identified during routine screening for DeltaF508. Two mutations were detected with a higher frequency than expected: 3272-26A-->G, which is the second most common mutation after DeltaF508 in our CF population with a frequency of 3.8%, and L927P (2.4%). The clinical data is presented for the mutations 186-2A-->G, E588V, 3272-26A-->G and L927P. The mutation data are useful for the Belgian population to supplement the initial screening set of mutations.

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0 High incidence of the CFTR mutations 3272-26A→G and L927P in Belgian cystic fibrosis patients, and identification of three new CFTR mutations (186-2A→G, E588V, and 1671insTATCA) Katrien Storm a,⁎, Els Moens b , Lieve Vits a , Haike De Vlieger a , Gino Delaere a , Maria D'Hollander a , Wim Wuyts a , Martine Biervliet a , Lutgardis Van Schil c , Kristine Desager b , Markus M. Nöthen a,1 a Department of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium b Department of Pediatrics, University Hospital of Antwerp, Antwerp, Belgium c Department of Pneumonology, Sint-Vincentiusziekenhuis, Antwerp, Belgium Accepted 10 October 2006 Available online 3 May 2007 Abstract We have analyzed 143 unrelated Belgian patients with a positive diagnosis of cystic fibrosis (CF) for mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Login to comment
5 Two mutations were detected with a higher frequency than expected: 3272-26A→G, which is the second most common mutation after ΔF508 in our CF population with a frequency of 3.8%, and L927P (2.4%). Login to comment
6 The clinical data is presented for the mutations 186-2A→G, E588V, 3272-26A→G and L927P. Login to comment
60 L927P (together with G542X and S1251N) is the fourth most common CFTR mutation, with a frequency of 2.4%. Login to comment
64 Also the incidence of the mutation L927P differs between different parts of Belgium and seems to be the highest for Antwerp (with frequencies from 0.3 up to 2.4%). Login to comment
76 L927P. Login to comment
77 The mutation L927P is caused by the transition of a T to C at nucleotide position 2912 in exon 15, and changes a leucine to a proline at position 927 of the protein. Login to comment
78 The L927P is described before by Hermans et al. [13] in 3 families (5 patients). Login to comment
79 They concluded that most likely L927P can be classified as a severe CF mutation comparable with ΔF508. Login to comment
80 We found L927P in 7 CF patients: four patients have ΔF508 as the second mutation, one patient 1717-1G→A, another patient S1251N, and a last patient 2789+ 5G→A. Login to comment
83 The patients described in Table 3 presented more gastro-intestinal problems and Table 2 Frequency of the mutations 3272-26A→G and L927P for different parts of Belgium and other countries Country/Region Frequency 3272-26A→G (%) Reference Belgium/Antwerp 3.8 This study Belgium/Brussels 1.7 W. Lissens, pers. comm. Belgium/Ghent 0.9 L. Messiaen, pers. comm. Belgium/Leuven 1.0 [14] The Netherlands 0.9 H. Scheffer, pers. comm. France 0.5 [15-17] Germany 0.9 [18] Greece 0.8 [19,20] Spain 0.5 [21] Canada (Toronto) 0.5 [22] Portugal 2.0 [11] South Africa (white population) 4.2 [23] Frequency L927P (%) Belgium/Antwerp 2.4 This study Belgium/Brussels 0.7 W. Lissens, pers. comm. Belgium/Gent 0.3 L. Messiaen, pers. comm. The Netherlands 0.5 [13] Table 3 Clinical phenotypes of patients compound heterozygous for L927P and a second mutation Genotype (L927P/any) Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6 Second mutation ΔF508 ΔF508 ΔF508 ΔF508 1717-1GNA S1251N Sex Male Female Male Female Female Female Age at diagnosis 1 month (meconium ileus) ? Login to comment
93 Children with L927P were mostly diagnosed in the neonatal period. Login to comment
94 From this, we conclude that patients with L927P show clinical features comparable to patients homozygous for ΔF508. Login to comment
114 Two known mutations 3272-26A→G and L927P were shown to occur with a higher frequency in Antwerp compared to other Belgian regions. Login to comment
115 We conclude that 3272-26ANG is a milder mutation than ΔF508, as reported before by Amaral et al. [12], and that L927P can be classified as a severe mutation comparable with ΔF508. Login to comment
116 Acknowledgements We would like to thank Dr. Sc. W. Lissens (Department of Medical Genetics, University Hospital of the Free University of Brussels, Belgium), Dr. Sc. L. Messiaen (Department of Medical Genetics, University Hospital of Ghent, Belgium; current address: Laboratory of Medical Genomics, University of Alabama, Birmingham, USA), and Dr. Sc. H. Scheffer (Department of Medical Genetics, University of Groningen, The Netherlands; current address: Department of Human Genetics, Radboud University Nijmegen Medical Center, The Netherlands) to communicate the information on the frequencies of the mutations 3272-26A→G and L927P in their CF population. Login to comment
81 We found L927P in 7 CF patients: four patients have ƊF508 as the second mutation, one patient 1717-1G࢐A, another patient S1251N, and a last patient 2789+ 5G࢐A. Login to comment
84 The patients described in Table 3 presented more gastro-intestinal problems and Table 2 Frequency of the mutations 3272-26A࢐G and L927P for different parts of Belgium and other countries Country/Region Frequency 3272-26A࢐G (%) Reference Belgium/Antwerp 3.8 This study Belgium/Brussels 1.7 W. Lissens, pers. comm. Belgium/Ghent 0.9 L. Messiaen, pers. comm. Belgium/Leuven 1.0 [14] The Netherlands 0.9 H. Scheffer, pers. comm. France 0.5 [15-17] Germany 0.9 [18] Greece 0.8 [19,20] Spain 0.5 [21] Canada (Toronto) 0.5 [22] Portugal 2.0 [11] South Africa (white population) 4.2 [23] Frequency L927P (%) Belgium/Antwerp 2.4 This study Belgium/Brussels 0.7 W. Lissens, pers. comm. Belgium/Gent 0.3 L. Messiaen, pers. comm. The Netherlands 0.5 [13] Table 3 Clinical phenotypes of patients compound heterozygous for L927P and a second mutation Genotype (L927P/any) Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6 Second mutation ƊF508 ƊF508 ƊF508 ƊF508 1717-1GNA S1251N Sex Male Female Male Female Female Female Age at diagnosis 1 month (meconium ileus) ? Login to comment
95 From this, we conclude that patients with L927P show clinical features comparable to patients homozygous for ƊF508. Login to comment
117 Acknowledgements We would like to thank Dr. Sc. W. Lissens (Department of Medical Genetics, University Hospital of the Free University of Brussels, Belgium), Dr. Sc. L. Messiaen (Department of Medical Genetics, University Hospital of Ghent, Belgium; current address: Laboratory of Medical Genomics, University of Alabama, Birmingham, USA), and Dr. Sc. H. Scheffer (Department of Medical Genetics, University of Groningen, The Netherlands; current address: Department of Human Genetics, Radboud University Nijmegen Medical Center, The Netherlands) to communicate the information on the frequencies of the mutations 3272-26A࢐G and L927P in their CF population. Login to comment

[hide] Identification of the L927P and delta L1260 mutati... Hum Mol Genet. 1994 Jul;3(7):1199-200. Hermans CJ, Veeze HJ, Drexhage VR, Halley DJ, van den Ouweland AM
Identification of the L927P and delta L1260 mutations in the CFTR gene.
Hum Mol Genet. 1994 Jul;3(7):1199-200., [PMID:7526927]

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21 Sequence analysis of exon 15 identified a substitution of T at position 2912 to a C resulting in a replacement of leucine by proline at position 927 (L927P). Login to comment
22 ASO hybridisation was performed to determine the frequency of the L927P mutation in our CF patient group using the oligomers: 5'-ACTTTGC- TTGCTATGG-3' (normal) and 5'-ACTTTGCCTGCTATGG-3' (mutant). Login to comment
25 The L927P mutation was not present in 60 non-CF chromosomes tested, indicating that L927P is very likely not a polymorphism. Login to comment
30 From the described clinical features we concluded that most likely both the L927P and AL1270 mutations can be classified as severe CF mutations comparable with AF508. Login to comment
32 Clinical features of CF patients with L927P and AL1260 CFTR mutations Family A patient 166 patient 290 Family B patient 246 Family C patient 221 patient 209 CF mutations Sex Age at diagnosis (yr) Current age (yr) Shwachman clinical score (max score r00)(7) Pancreatic insufficiency FEVt (% predicted) Onset of Pseudomonas colonization (yr) AF5O8/L927P male 3.7 15.2 80 yes 65 15.0 AF5O8/L927P female 1.0 13.6 85 yes 60 - AF508/L927P male 0.2 3.3 90 yes - AL1260/L927P female 0.6 21.0 80 yes 50 6.8 AL1260/L927P female 9.0' 18.7 75 yes 65 13.0 Patients 290 and 166 as well as patient 221 and 209 are siblings. Login to comment

[hide] A functional CFTR assay using primary cystic fibro... Nat Med. 2013 Jul;19(7):939-45. doi: 10.1038/nm.3201. Epub 2013 Jun 2. Dekkers JF, Wiegerinck CL, de Jonge HR, Bronsveld I, Janssens HM, de Winter-de Groot KM, Brandsma AM, de Jong NW, Bijvelds MJ, Scholte BJ, Nieuwenhuis EE, van den Brink S, Clevers H, van der Ent CK, Middendorp S, Beekman JM
A functional CFTR assay using primary cystic fibrosis intestinal organoids.
Nat Med. 2013 Jul;19(7):939-45. doi: 10.1038/nm.3201. Epub 2013 Jun 2., [PMID:23727931]

Abstract [show]
We recently established conditions allowing for long-term expansion of epithelial organoids from intestine, recapitulating essential features of the in vivo tissue architecture. Here we apply this technology to study primary intestinal organoids of people suffering from cystic fibrosis, a disease caused by mutations in CFTR, encoding cystic fibrosis transmembrane conductance regulator. Forskolin induces rapid swelling of organoids derived from healthy controls or wild-type mice, but this effect is strongly reduced in organoids of subjects with cystic fibrosis or in mice carrying the Cftr F508del mutation and is absent in Cftr-deficient organoids. This pattern is phenocopied by CFTR-specific inhibitors. Forskolin-induced swelling of in vitro-expanded human control and cystic fibrosis organoids corresponds quantitatively with forskolin-induced anion currents in freshly excised ex vivo rectal biopsies. Function of the CFTR F508del mutant protein is restored by incubation at low temperature, as well as by CFTR-restoring compounds. This relatively simple and robust assay will facilitate diagnosis, functional studies, drug development and personalized medicine approaches in cystic fibrosis.

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127 (d) Forskolin-induced swelling of rectal organoids derived from three individual healthy controls, two individuals with a mild cystic fibrosis genotype (F508del A455E) and nine individuals with a severe cystic fibrosis genotype (one individual with E60X 4015ATTTdel, one with F508del G542X, one with F508del L927P and six with F508del F508del). Login to comment
150 0 500 1,000 1,500 2,000 2,500 0 500 1,000 1,500 2,000 2,500 3,000 0 400 800 1,200 1,600 C8 Corr-4a C8 + Corr-4a VX-809 VX-770 VX-809 + VX-770 VRT-325 Corr-4a VRT-325 + Corr-4a CF1 CF6 CF5 CF4 CF3 CF2 F508del L927P F508del G542X E60X 4015delATTT F508del F508del b d a c 0 20 40 60 80 100 120 V R T - 3 2 5 C o r r - 4 a C 8 V X - 8 0 9 V X - 7 7 0 V R T - 3 2 5 + C o r r - 4 a C 8 + C o r r - 4 a V X - 8 0 9 + V X - 7 7 0 C o n t r o l C o n t r o l F508del F508del HC F508del A455E Organoid swelling (absolute AUC t = 60) Organoid swelling (absolute AUC t = 60) Organoid swelling (absolute AUC t = 60) Organoid swelling (normalized AUC t = 60) Figure 5ߒ Differential FIS between organoids from subjects with cystic fibrosis after chemical CFTR restoration. Login to comment
332 Hermans, C.J., Veeze, H.J., Drexhage, V.R., Halley, D.J. & van den Ouweland, A.M. Identification of the L927P and ࢞L1260 mutations in the CFTR gene. Login to comment
390 Rectal organoids from healthy controls and subjects with cystic fibrosis were generated from four rectal suction biopsies after ICMs obtained (i) during standard cystic fibrosis care (one individual each harboring E60X 4015ATTTdel, F508del G542X or F508del L927P and five individuals harboring F508del F508del), (ii) for diagnostic purposes (one healthy control) or (iii) during voluntary participation in studies approved by the University Medical Center Utrecht and Erasmus MC ethics committees (two healthy controls and one individual harboring F508del F508del). Login to comment

[hide] Effect of ivacaftor on CFTR forms with missense mu... J Cyst Fibros. 2014 Jan;13(1):29-36. doi: 10.1016/j.jcf.2013.06.008. Epub 2013 Jul 23. Van Goor F, Yu H, Burton B, Hoffman BJ
Effect of ivacaftor on CFTR forms with missense mutations associated with defects in protein processing or function.
J Cyst Fibros. 2014 Jan;13(1):29-36. doi: 10.1016/j.jcf.2013.06.008. Epub 2013 Jul 23., [PMID:23891399]

Abstract [show]
BACKGROUND: Ivacaftor (KALYDECO, VX-770) is a CFTR potentiator that increased CFTR channel activity and improved lung function in patients age 6 years and older with CF who have the G551D-CFTR gating mutation. The aim of this in vitro study was to evaluate the effect of ivacaftor on mutant CFTR protein forms with defects in protein processing and/or channel function. METHODS: The effect of ivacaftor on CFTR function was tested in electrophysiological studies using a panel of Fischer rat thyroid (FRT) cells expressing 54 missense CFTR mutations that cause defects in the amount or function of CFTR at the cell surface. RESULTS: Ivacaftor potentiated multiple mutant CFTR protein forms that produce functional CFTR at the cell surface. These included mutant CFTR forms with mild defects in CFTR processing or mild defects in CFTR channel conductance. CONCLUSIONS: These in vitro data indicated that ivacaftor is a broad acting CFTR potentiator and could be used to help stratify patients with CF who have different CFTR genotypes for studies investigating the potential clinical benefit of ivacaftor.

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No. Sentence Comment
44 None M1V A46D E56K P67L R74W G85E E92K D110E D110H R117C R117H E193K L206W R334W I336K T338I S341P R347H R347P R352Q A455E L467P S492F F508del V520F A559T R560S R560T A561E Y569D D579G R668C L927P S945L S977F L997F F1052V H1054D K1060T L1065P R1066C R1066H R1066M A1067T R1070Q R1070W F1074L L1077P H1085R M1101K D1152H S1235R D1270N N1303K 0 100 200 300 400 500 600 * * * CFTR Mutation mRNA (% Normal CFTR) Fig. 1. Login to comment
64 Mutant CFTR form CFTR processing Mature/total % Normal CFTR Normal 0.89 &#b1; 0.01 100.0 &#b1; 18.5 G85E -0.05 &#b1; 0.04 -1.0 &#b1; 0.9 R560S 0.00 &#b1; 0.00 0.0 &#b1; 0.0 R1066C 0.02 &#b1; 0.01 0.0 &#b1; 0.0 S492F 0.00 &#b1; 0.00 0.1 &#b1; 0.1 R560T 0.01 &#b1; 0.01 0.2 &#b1; 0.1 V520F 0.05 &#b1; 0.03 0.3 &#b1; 0.2 M1101K 0.05 &#b1; 0.03 0.3 &#b1; 0.1 A561E 0.08 &#b1; 0.04 0.5 &#b1; 0.2 R1066M 0.02 &#b1; 0.02 0.5 &#b1; 0.4 N1303K 0.02 &#b1; 0.02 0.5 &#b1; 0.3 A559T 0.16 &#b1; 0.09 0.6 &#b1; 0.2 M1V 0.06 &#b1; 0.06 0.7 &#b1; 0.6 Y569D 0.11 &#b1; 0.04 0.6 &#b1; 0.2 R1066H 0.08 &#b1; 0.02a 0.7 &#b1; 0.2a L1065P 0.05 &#b1; 0.05 1.0 &#b1; 0.8 L467P 0.10 &#b1; 0.07 1.2 &#b1; 0.8 L1077P 0.08 &#b1; 0.04 1.5 &#b1; 0.6 A46D 0.21 &#b1; 0.08 1.9 &#b1; 0.5a E92K 0.06 &#b1; 0.05 1.9 &#b1; 1.3 H1054D 0.09 &#b1; 0.04 1.9 &#b1; 0.8 F508del 0.09 &#b1; 0.02a 2.3 &#b1; 0.5a H1085R 0.06 &#b1; 0.01a 3.0 &#b1; 0.7a I336K 0.42 &#b1; 0.05a 6.5 &#b1; 0.7a L206W 0.35 &#b1; 0.10a 6.8 &#b1; 1.7a F1074L 0.52 &#b1; 0.03a 10.9 &#b1; 0.6a A455E 0.26 &#b1; 0.10a 11.5 &#b1; 2.5a E56K 0.29 &#b1; 0.04a 12.2 &#b1; 1.5a R347P 0.48 &#b1; 0.04a 14.6 &#b1; 1.8a R1070W 0.61 &#b1; 0.04a 16.3 &#b1; 0.6a P67L 0.36 &#b1; 0.04a 28.4 &#b1; 6.8a R1070Q 0.90 &#b1; 0.01a 29.5 &#b1; 1.4a S977F 0.97 &#b1; 0.01a 37.3 &#b1; 2.4a A1067T 0.78 &#b1; 0.03a 38.6 &#b1; 6.1a D579G 0.72 &#b1; 0.02a 39.3 &#b1; 3.1a D1270N 1.00 &#b1; 0.00a,c 40.7 &#b1; 1.2a S945L 0.65 &#b1; 0.04a 42.4 &#b1; 8.9a L927P 0.89 &#b1; 0.01a,b 43.5 &#b1; 2.5a,b R117C 0.87 &#b1; 0.02a,b 49.1 &#b1; 2.9a,b T338I 0.93 &#b1; 0.03a,b 54.2 &#b1; 3.7a,b L997F 0.90 &#b1; 0.04a,b 59.8 &#b1; 10.4a,b D110H 0.97 &#b1; 0.01a,b 60.6 &#b1; 1.5a,b S341P 0.79 &#b1; 0.02a 65.0 &#b1; 4.9a,b R668C 0.94 &#b1; 0.03a,b 68.5 &#b1; 1.9a,b R74W 0.78 &#b1; 0.01a 69.0 &#b1; 2.7a,b D110E 0.92 &#b1; 0.05a,b 87.5 &#b1; 9.5a,b R334W 0.91 &#b1; 0.05a,b 97.6 &#b1; 10.0a,b K1060T 0.87 &#b1; 0.02a,b 109.9 &#b1; 28.0a,b R347H 0.96 &#b1; 0.02a,c 120.7 &#b1; 2.8a,b S1235R 0.96 &#b1; 0.00a,c 139.0 &#b1; 9.0a,b E193K 0.84 &#b1; 0.02a,b 143.0 &#b1; 17.1a,b R117H 0.86 &#b1; 0.01a,b 164.5 &#b1; 34.2a,b R352Q 0.98 &#b1; 0.01a,b 179.9 &#b1; 8.0a,c F1052V 0.90 &#b1; 0.01a,b 189.9 &#b1; 33.1a,b D1152H 0.96 &#b1; 0.02a,c 312.0 &#b1; 45.5a,b Notes to Table 1: Quantification of steady-state CFTR maturation expressed as the mean (&#b1;SEM; n = 5-9) ratio of mature CFTR to total CFTR (immature plus mature) or level of mature mutant CFTR relative to mature normal-CFTR (% normal CFTR) in FRT cells individually expressing CFTR mutations. Login to comment
74 Because the level of CFTR mRNA was similar across the panel of cell lines tested, the range in baseline activity and ivacaftor response likely reflects the severity of the functional defect and/or the 0 50 100 150 200 S341P R347P L467P S492F A559T A561E Y569D L1065P R1066C R1066M L1077P M1101K N1303K R560S L927P R560T H1085R V520F E92K M1V F508del H1054D I336K A46D G85E R334W T338I R1066H R352Q R117C L206W R347H S977F S945L A455E F1074L E56K P67L R1070W D110H D579G D110E R1070Q L997F A1067T E193K R117H R74W K1060T R668C D1270N D1152H S1235R F1052V Baseline With ivacaftor * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Chloride transport (% Normal) Mutant CFTR form 0 100 200 300 400 S341P R347P L467P S492F A559T A561E Y569D L1065P R1066C R1066M L1077P M1101K N1303K R560S L927P R560T H1085R V520F E92K M1V F508del H1054D I336K A46D G85E R334W T338I R1066H R352Q R117C L206W R347H S977F S945L A455E F1074L P67L E56K R1070W D110H D579G D110E R1070Q L997F A1067T E193K R117H R74W K1060T R668C D1270N D1152H S1235R F1052V * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Mature CFTR (% Normal) Mutant CFTR form A B Fig. 2. Login to comment
82 Mutation Patientsa Chloride transport (bc;A/cm2 ) Chloride transport (% normal) EC50 Baseline With ivacaftor Baseline With ivacaftor Fold increase over baselineb Normal 204.5 &#b1; 33.3 301.3 &#b1; 33.8c 100.0 &#b1; 16.3 147.3 &#b1; 16.5c 1.5 266 &#b1; 42 G551D 1282 1.5 &#b1; 0.7 113.2 &#b1; 13.0c 1.0 &#b1; 0.5 55.3 &#b1; 6.3c 55.3 312 &#b1; 73 F1052V 12 177.3 &#b1; 13.7 410.2 &#b1; 11.3c 86.7 &#b1; 6.7 200.7 &#b1; 5.6c 2.3 177 &#b1; 14 S1235R ND 160.6 &#b1; 25.7 352.1 &#b1; 43.4c 78.5 &#b1; 12.6 172.2 &#b1; 21.2c 2.2 282 &#b1; 104 D1152H 185 117.3 &#b1; 23.0 282.7 &#b1; 46.9c 57.4 &#b1; 11.2 138.2 &#b1; 22.9c 2.4 178 &#b1; 67 D1270N 32 109.5 &#b1; 20.5 209.5 &#b1; 27.4c 53.6 &#b1; 10.0 102.4 &#b1; 13.4c 1.9 254 &#b1; 56 R668C 45 99.0 &#b1; 9.4 217.6 &#b1; 11.7c 48.4 &#b1; 4.6 106.4 &#b1; 5.7c 2.2 517 &#b1; 105 K1060T ND 89.0 &#b1; 9.8 236.4 &#b1; 20.3c 43.5 &#b1; 4.8 115.6 &#b1; 9.9c 2.7 131 &#b1; 73 R74W 25 86.8 &#b1; 26.9 199.1 &#b1; 16.8c 42.5 &#b1; 13.2 97.3 &#b1; 8.2c 2.3 162 &#b1; 17 R117H 739 67.2 &#b1; 13.3 274.1 &#b1; 32.2c 32.9 &#b1; 6.5 134.0 &#b1; 15.7c 4.1 151 &#b1; 14 E193K ND 62.2 &#b1; 9.8 379.1 &#b1; 1.1c 30.4 &#b1; 4.8 185.4 &#b1; 1.0c 6.1 240 &#b1; 20 A1067T ND 55.9 &#b1; 3.2 164.0 &#b1; 9.7c 27.3 &#b1; 1.6 80.2 &#b1; 4.7c 2.9 317 &#b1; 214 L997F 27 43.7 &#b1; 3.2 145.5 &#b1; 4.0c 21.4 &#b1; 1.6 71.2 &#b1; 2.0c 3.3 162 &#b1; 12 R1070Q 15 42.0 &#b1; 0.8 67.3 &#b1; 2.9c 20.6 &#b1; 0.4 32.9 &#b1; 1.4c 1.6 164 &#b1; 20 D110E ND 23.3 &#b1; 4.7 96.4 &#b1; 15.6c 11.4 &#b1; 2.3 47.1 &#b1; 7.6c 4.1 213 &#b1; 51 D579G 21 21.5 &#b1; 4.1 192.0 &#b1; 18.5c 10.5 &#b1; 2.0 93.9 &#b1; 9.0c 8.9 239 &#b1; 48 D110H 30 18.5 &#b1; 2.2 116.7 &#b1; 11.3c 9.1 &#b1; 1.1 57.1 &#b1; 5.5c 6.2 249 &#b1; 59 R1070W 13 16.6 &#b1; 2.6 102.1 &#b1; 3.1c 8.1 &#b1; 1.3 49.9 &#b1; 1.5c 6.2 158 &#b1; 48 P67L 53 16.0 &#b1; 6.7 88.7 &#b1; 15.7c 7.8 &#b1; 3.3 43.4 &#b1; 7.7c 5.6 195 &#b1; 40 E56K ND 15.8 &#b1; 3.1 63.6 &#b1; 4.4c 7.7 &#b1; 1.5 31.1 &#b1; 2.2c 4.0 123 &#b1; 33 F1074L ND 14.0 &#b1; 3.4 43.5 &#b1; 5.4c 6.9 &#b1; 1.6 21.3 &#b1; 2.6c 3.1 141 &#b1; 19 A455E 120 12.9 &#b1; 2.6 36.4 &#b1; 2.5c 6.3 &#b1; 1.2 17.8 &#b1; 1.2c 2.8 170 &#b1; 44 S945L 63 12.3 &#b1; 3.9 154.9 &#b1; 47.6c 6.0 &#b1; 1.9 75.8 &#b1; 23.3c 12.6 181 &#b1; 36 S977F 9 11.3 &#b1; 6.2 42.5 &#b1; 19.1c 5.5 &#b1; 3.0 20.8 &#b1; 9.3c 3.8 283 &#b1; 36 R347H 65 10.9 &#b1; 3.3 106.3 &#b1; 7.6c 5.3 &#b1; 1.6 52.0 &#b1; 3.7c 9.8 280 &#b1; 35 L206W 81 10.3 &#b1; 1.7 36.4 &#b1; 2.8c 5.0 &#b1; 0.8 17.8 &#b1; 1.4c 3.6 101 &#b1; 13 R117C 61 5.8 &#b1; 1.5 33.7 &#b1; 7.8c 2.9 &#b1; 0.7 16.5 &#b1; 3.8c 5.7 380 &#b1; 136 R352Q 46 5.5 &#b1; 1.0 84.5 &#b1; 7.8c 2.7 &#b1; 0.5 41.3 &#b1; 3.8c 15.2 287 &#b1; 75 R1066H 29 3.0 &#b1; 0.3 8.0 &#b1; 0.8c 1.5 &#b1; 0.1 3.9 &#b1; 0.4c 2.6 390 &#b1; 179 T338I 54 2.9 &#b1; 0.8 16.1 &#b1; 2.4c 1.4 &#b1; 0.4 7.9 &#b1; 1.2c 5.6 334 &#b1; 38 R334W 150 2.6 &#b1; 0.5 10.0 &#b1; 1.4c 1.3 &#b1; 0.2 4.9 &#b1; 0.7c 3.8 259 &#b1; 103 G85E 262 1.6 &#b1; 1.0 1.5 &#b1; 1.2 0.8 &#b1; 0.5 0.7 &#b1; 0.6 NS NS A46D ND 2.0 &#b1; 0.6 1.1 &#b1; 1.1 1.0 &#b1; 0.3 0.5 &#b1; 0.6 NS NS I336K 29 1.8 &#b1; 0.2 7.4 &#b1; 0.1c 0.9 &#b1; 0.1 3.6 &#b1; 0.1c 4 735 &#b1; 204 H1054D ND 1.7 &#b1; 0.3 8.7 &#b1; 0.3c 0.8 &#b1; 0.1 4.2 &#b1; 0.1c 5.3 187 &#b1; 20 F508del 29,018 0.8 &#b1; 0.6 12.1 &#b1; 1.7c 0.4 &#b1; 0.3 5.9 &#b1; 0.8c 14.8 129 &#b1; 38 M1V 9 0.7 &#b1; 1.4 6.5 &#b1; 1.9c 0.4 &#b1; 0.7 3.2 &#b1; 0.9c 8.0 183 &#b1; 85 E92K 14 0.6 &#b1; 0.2 4.3 &#b1; 0.8c 0.3 &#b1; 0.1 2.1 &#b1; 0.4c 7.0 198 &#b1; 46 V520F 58 0.4 &#b1; 0.2 0.5 &#b1; 0.2 0.2 &#b1; 0.1 0.2 &#b1; 0.1 NS NS H1085R ND 0.3 &#b1; 0.2 2.1 &#b1; 0.4 0.2 &#b1; 0.1 1.0 &#b1; 0.2 NS NS R560T 180 0.3 &#b1; 0.3 0.5 &#b1; 0.5 0.1 &#b1; 0.1 0.2 &#b1; 0.2 NS NS L927P 15 0.2 &#b1; 0.1 10.7 &#b1; 1.7c 0.1 &#b1; 0.1 5.2 &#b1; 0.8c 52.0 313 &#b1; 66 R560S ND 0.0 &#b1; 0.1 -0.2 &#b1; 0.2 0.0 &#b1; 0.0 -0.1 &#b1; 0.1 NS NS N1303K 1161 0.0 &#b1; 0.0 1.7 &#b1; 0.3 0.0 &#b1; 0.0 0.8 &#b1; 0.2 NS NS M1101K 79 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS L1077P 42 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS R1066M ND 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS R1066C 100 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS L1065P 25 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS Y569D 9 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS A561E ND 0.0 &#b1; 0.1 0.0 &#b1; 0.1 0.0 &#b1; 0.0 0.0 &#b1; 0.1 NS NS A559T 43 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS S492F 16 0.0 &#b1; 0.0 1.7 &#b1; 1.2 0.0 &#b1; 0.0 0.8 &#b1; 0.6 NS NS L467P 16 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS R347P 214 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 0.0 &#b1; 0.0 NS NS S341P 9 0.0 &#b1; 0.0 0.2 &#b1; 0.2 0.0 &#b1; 0.0 0.1 &#b1; 0.1 NS NS a Number of individuals with the individual mutation in the CFTR-2 database (www.CFTR2.org). Login to comment

[hide] Full-open and closed CFTR channels, with lateral t... Cell Mol Life Sci. 2015 Apr;72(7):1377-403. doi: 10.1007/s00018-014-1749-2. Epub 2014 Oct 7. Mornon JP, Hoffmann B, Jonic S, Lehn P, Callebaut I
Full-open and closed CFTR channels, with lateral tunnels from the cytoplasm and an alternative position of the F508 region, as revealed by molecular dynamics.
Cell Mol Life Sci. 2015 Apr;72(7):1377-403. doi: 10.1007/s00018-014-1749-2. Epub 2014 Oct 7., [PMID:25287046]

Abstract [show]
In absence of experimental 3D structures, several homology models, based on ABC exporter 3D structures, have provided significant insights into the molecular mechanisms underlying the function of the cystic fibrosis transmembrane conductance regulator (CFTR) protein, a chloride channel whose defects are associated with cystic fibrosis (CF). Until now, these models, however, did not furnished much insights into the continuous way that ions could follow from the cytosol to the extracellular milieu in the open form of the channel. Here, we have built a refined model of CFTR, based on the outward-facing Sav1866 experimental 3D structure and integrating the evolutionary and structural information available today. Molecular dynamics simulations revealed significant conformational changes, resulting in a full-open channel, accessible from the cytosol through lateral tunnels displayed in the long intracellular loops (ICLs). At the same time, the region of nucleotide-binding domain 1 in contact with one of the ICLs and carrying amino acid F508, the deletion of which is the most common CF-causing mutation, was found to adopt an alternative but stable position. Then, in a second step, this first stable full-open conformation evolved toward another stable state, in which only a limited displacement of the upper part of the transmembrane helices leads to a closure of the channel, in a conformation very close to that adopted by the Atm1 ABC exporter, in an inward-facing conformation. These models, supported by experimental data, provide significant new insights into the CFTR structure-function relationships and into the possible impact of CF-causing mutations.

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351 As already hinted to above, only two mutations are observed in MSD2, L927P, and M1101K, which both might disturb the conformation and behavior of the transmembrane helices within the lipid bilayer. Login to comment

[hide] The improvement of the best practice guidelines fo... Eur J Hum Genet. 2015 May 27. doi: 10.1038/ejhg.2015.99. Girardet A, Viart V, Plaza S, Daina G, De Rycke M, Des Georges M, Fiorentino F, Harton G, Ishmukhametova A, Navarro J, Raynal C, Renwick P, Saguet F, Schwarz M, SenGupta S, Tzetis M, Roux AF, Claustres M
The improvement of the best practice guidelines for preimplantation genetic diagnosis of cystic fibrosis: toward an international consensus.
Eur J Hum Genet. 2015 May 27. doi: 10.1038/ejhg.2015.99., [PMID:26014425]

Abstract [show]
Cystic fibrosis (CF) is one of the most common indications for preimplantation genetic diagnosis (PGD) for single gene disorders, giving couples the opportunity to conceive unaffected children without having to consider termination of pregnancy. However, there are no available standardized protocols, so that each center has to develop its own diagnostic strategies and procedures. Furthermore, reproductive decisions are complicated by the diversity of disease-causing variants in the CFTR (cystic fibrosis transmembrane conductance regulator) gene and the complexity of correlations between genotypes and associated phenotypes, so that attitudes and practices toward the risks for future offspring can vary greatly between countries. On behalf of the EuroGentest Network, eighteen experts in PGD and/or molecular diagnosis of CF from seven countries attended a workshop held in Montpellier, France, on 14 December 2011. Building on the best practice guidelines for amplification-based PGD established by ESHRE (European Society of Human Reproduction and Embryology), the goal of this meeting was to formulate specific guidelines for CF-PGD in order to contribute to a better harmonization of practices across Europe. Different topics were covered including variant nomenclature, inclusion criteria, genetic counseling, PGD strategy and reporting of results. The recommendations are summarized here, and updated information on the clinical significance of CFTR variants and associated phenotypes is presented.European Journal of Human Genetics advance online publication, 27 May 2015; doi:10.1038/ejhg.2015.99.

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79 (unknown) Q39X c.115C4T p.Gln39* P67L c.200C4T p.Pro67Leu R75X c.223C4T p.Arg75* 405+1G4A c.273+1G4A 406-1G4A c.274-1G4A E92X c.274G4T p.Glu92* E92K c.274G4A p.Glu92Lys Q98X c.292C4T p.Gln98* 457TAT4G c.325_327delTATinsG p.Tyr109Glyfs*4 D110H c.328G4C p.Asp110His R117C c.349C4T p.Arg117Cys Y122X c.366 T4A p.Tyr122* 574delA c.442delA p.Ile148Leufs*5 444delA c.313delA p.Ile105Serfs*2 663delT c.531delT p.Ile177Metfs*12 G178R c.532G4A p.Gly178Arg 711+3 A4G c.579+3 A4G 711+5G4A c.579+5G4A 712-1G4T c.580-1G4T H199Y c.595C4T p.His199Tyr P205S c.613C4T p.Pro205Ser L206W c.617 T4G p.Leu206Trp Q220X c.658C4T p.Gln220* 852del22 c.720_741delAGGGAGAAT GATGATGAAGTAC p.Gly241Glufs*13 1078delT c.948delT p.Phe316Leufs*12 G330X c.988G4T p.Gly330* Table 1 (Continued ) HGVS nomenclature Legacy name cDNA nucleotide name Protein name R334W c.1000C4T p.Arg334Trp I336K c.1007 T4A p.Ile336Lys T338I c.1013C4T p.Thr338Ile 1154insTC c.1021_1022dupTC p.Phe342Hisfs*28 S341P c.1021 T4C p.Ser341Pro R347H c.1040G4A p.Arg347His 1213delT c.1081delT p.Trp361Glyfs*8 1248+1G4A c.1116+1G4A 1259insA c.1130dupA p.Gln378Alafs*4 W401X(TAG) c.1202G4A p.Trp401* W401X(TGA) c.1203G4A p.Trp401* 1341+1G4A c.1209+1G4A 1461ins4 c.1329_1330insAGAT p.Ile444Argfs*3 1525-1G4A c.1393-1G4A S466X c.1397C4A or c.1397C4G p.Ser466* L467P c.1400 T4C p.Leu467Pro S489X c.1466C4A p.Ser489* S492F c.1475C4T p.Ser492Phe 1677delTA c.1545_1546delTA p.Tyr515* V520F c.1558G4T p.Val520Phe 1717-1G4A c.1585-1G4A 1717-8G4A c.1585-8G4A S549R c.1645 A4C p.Ser549Arg S549N c.1646G4A p.Ser549Asn S549R c.1647 T4G p.Ser549Arg Q552X c.1654C4T p.Gln552* A559T c.1675G4A p.Ala559Thr 1811+1.6kbA4G c.1680-886 A4G 1812-1G4A c.1680-1G4A R560K c.1679G4A p.Arg560Lys E585X c.1753G4T p.Glu585* 1898+3 A4G c.1766+3 A4G 2143delT c.2012delT p.Leu671* 2184insA c.2052_2053insA p.Gln685Thrfs*4 2184delA c.2052delA p.Lys684Asnfs*38 R709X c.2125C4T p.Arg709* K710X c.2128 A4T p.Lys710* 2307insA c.2175dupA p.Glu726Argfs*4 L732X c.2195 T4G p.Leu732* 2347delG c.2215delG p.Val739Tyrfs*16 R764X c.2290C4T p.Arg764* 2585delT c.2453delT p.Leu818Trpfs*3 E822X c.2464G4T p.Glu822* 2622+1G4A c.2490+1G4A E831X c.2491G4T p.Glu831* W846X c.2537G4A p.Trp846* W846X (2670TGG4TGA) c.2538G4A p.Trp846* R851X c.2551C4T p.Arg851* 2711delT c.2583delT p.Phe861Leufs*3 S945L c.2834C4T p.Ser945Leu 2789+2insA c.2657+2_2657+3insA Q890X c.2668C4T p.Gln890* L927P c.2780 T4C p.Leu927Pro 3007delG c.2875delG p.Ala959Hisfs*9 G970R c.2908G4C p.Gly970Arg 3120G4A c.2988G4A function variants that cause CF disease when paired together; (ii) variants that retain residual CFTR function and are compatible with milder phenotypes such as CFTR-RD; (iii) variants with no clinical consequences; and (iv) variants of unproven or uncertain clinical relevance. Login to comment