rs376968326
Variant summary
Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate
The NM_000492.4(CFTR):āc.3274T>Cā(p.Tyr1092His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000954 in 1,613,466 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_000492.4 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_pathogenic. Variant got 6 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
CFTR | NM_000492.4 | c.3274T>C | p.Tyr1092His | missense_variant | Exon 20 of 27 | ENST00000003084.11 | NP_000483.3 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.000118 AC: 18AN: 152020Hom.: 1 Cov.: 31
GnomAD3 exomes AF: 0.0000239 AC: 6AN: 251172Hom.: 0 AF XY: 0.0000368 AC XY: 5AN XY: 135740
GnomAD4 exome AF: 0.0000931 AC: 136AN: 1461446Hom.: 0 Cov.: 31 AF XY: 0.0000922 AC XY: 67AN XY: 727026
GnomAD4 genome AF: 0.000118 AC: 18AN: 152020Hom.: 1 Cov.: 31 AF XY: 0.0000539 AC XY: 4AN XY: 74236
ClinVar
Submissions by phenotype
not provided Uncertain:4
The CFTR c.3274T>C; p.Tyr1092His variant (rs376968326) is reported in the literature in the compound heterozygous state with a known pathogenic variant in individuals affected with cystic fibrosis (Prontera 2016, Trujillano 2013). This variant is reported in ClinVar (Variation ID: 495930), and is only observed on seven alleles in the Genome Aggregation Database, indicating it is not a common polymorphism. The tyrosine at codon 1092 is highly conserved, and computational analyses (SIFT, PolyPhen-2) predict that this variant is deleterious. However, given the limited clinical data and lack of functional data, the significance of the p.Tyr1092His variant is uncertain at this time. References: Prontera P et al. A Clinical and Molecular Survey of 62 Cystic Fibrosis Patients from Umbria (Central Italy) Disclosing a High Frequency (2.4%) of the 2184insA Allele: Implications for Screening. Public Health Genomics. 2016;19(6):336-341. Trujillano D et al. Next generation diagnostics of cystic fibrosis and CFTR-related disorders by targeted multiplex high-coverage resequencing of CFTR. J Med Genet. 2013;50(7):455-462. -
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In silico analysis supports that this missense variant does not alter protein structure/function; Observed with a pathogenic variant in an individual with cystic fibrosis in published literature, but it is not known whether the variants occurred on the same (in cis) or on different (in trans) chromosomes (Prontera 2016); This variant is associated with the following publications: (PMID: 23687349, 27728908, 25087612) -
Cystic fibrosis Pathogenic:1Uncertain:2
This sequence change replaces tyrosine, which is neutral and polar, with histidine, which is basic and polar, at codon 1092 of the CFTR protein (p.Tyr1092His). This variant is present in population databases (rs376968326, gnomAD 0.006%). This missense change has been observed in individuals with cystic fibrosis (PMID: 23687349, 27728908, 35273129). ClinVar contains an entry for this variant (Variation ID: 495930). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CFTR protein function with a positive predictive value of 80%. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -
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The p.Y1092H variant (also known as c.3274T>C), located in coding exon 20 of the CFTR gene, results from a T to C substitution at nucleotide position 3274. The tyrosine at codon 1092 is replaced by histidine, an amino acid with similar properties. This variant has been reported in one individual from a cystic fibrosis (CF) cohort in conjunction with an intronic CFTR deletion and in a second CF cohort in an individual in conjunction with the CFTR p.F508del mutation; however, information regarding phase was not provided and clinical details were limited (Trujillano D et al. J. Med. Genet., 2013 Jul;50:455-62; Prontera P et al. Public Health Genomics, 2016 Oct;19:336-341). This variant has also been detected in an exome cohort with limited clinical details provided (Tabor HK et al. Am. J. Hum. Genet., 2014 Aug;95:183-93). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
CFTR-related disorder Uncertain:2
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The CFTR c.3274T>C variant is predicted to result in the amino acid substitution p.Tyr1092His. This variant has been reported in two patients with cystic fibrosis (Table S3, Trujillano et al. 2013. PubMed ID: 23687349; Table 1, Prontera et al. 2016. PubMed ID: 27728908) and in one patient with bronchiectasis (https://www.redalyc.org/journal/6357/635766604013/html/). This variant was also found in a patient with unknown phenotype as part of a newborn screening program (Tabor et al. 2014. PubMed ID: 25087612). However, no further evidence of its pathogenicity was provided regarding segregation with disease in families or functional data. This variant is reported in 0.0047% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/7-117251769-T-C). Although we suspect that this variant may be pathogenic, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
not specified Uncertain:1
Variant summary: CFTR c.3274T>C (p.Tyr1092His) results in a conservative amino acid change located in the ABC transporter type 1, transmembrane domain (IPR011527) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2.4e-05 in 251172 control chromosomes. c.3274T>C has been reported in the literature in individuals affected with Cystic Fibrosis in compound heterozygosity with known- or likely pathogenic variants (Trujillano_2013, Prontera_2016). These data indicate that the variant may be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect resulted in approximately (18.5)% of normal chloride channel conductance relative to wild type (e.g., Bihler_2024). The following publications have been ascertained in the context of this evaluation (PMID: 26990548, 34140271, 38388235, 35273129, 11504857, 27728908, 25735457, 25087612, 23687349). ClinVar contains an entry for this variant (Variation ID: 495930). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -
Cystic fibrosis;C0238339:Hereditary pancreatitis;C0403814:Congenital bilateral aplasia of vas deferens from CFTR mutation;C2749757:Bronchiectasis with or without elevated sweat chloride 1 Uncertain:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at