7-117540282-C-T

Position:

chr7-117540282-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate

The NM_000492.4(CFTR):c.1052C>T(p.Thr351Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,613,896 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T351S) has been classified as Benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

CFTR
NM_000492.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:6

Conservation

PhyloP100: 7.43

Variant links:

Genes affected

CFTR (HGNC:1884): (CF transmembrane conductance regulator) This gene encodes a member of the ATP-binding cassette (ABC) transporter superfamily. The encoded protein functions as a chloride channel, making it unique among members of this protein family, and controls ion and water secretion and absorption in epithelial tissues. Channel activation is mediated by cycles of regulatory domain phosphorylation, ATP-binding by the nucleotide-binding domains, and ATP hydrolysis. Mutations in this gene cause cystic fibrosis, the most common lethal genetic disorder in populations of Northern European descent. The most frequently occurring mutation in cystic fibrosis, DeltaF508, results in impaired folding and trafficking of the encoded protein. Multiple pseudogenes have been identified in the human genome. [provided by RefSeq, Aug 2017]

CFTR links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM1

In a transmembrane_region Helical; Name=6 (size 18) in uniprot entity CFTR_HUMAN there are 9 pathogenic changes around while only 1 benign (90%) in NM_000492.4

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.923

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CFTR	NM_000492.4 linkuse as main transcript	c.1052C>T	p.Thr351Ile	missense_variant	8/27	ENST00000003084.11	NP_000483.3	P13569-1A0A024R730

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CFTR	ENST00000003084.11 linkuse as main transcript	c.1052C>T	p.Thr351Ile	missense_variant	8/27	1	NM_000492.4	ENSP00000003084.6		P13569-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152164

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251162

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135728

show subpopulations

Gnomad AFR exome

AF:

0.000123

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000274

AC:

AN:

1461732

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727178

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000270

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152164

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74344

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:6

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Cystic fibrosis

Pathogenic:1Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Nov 21, 2023	This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 351 of the CFTR protein (p.Thr351Ile). This variant is present in population databases (rs1800086, gnomAD 0.008%). This variant has not been reported in the literature in individuals affected with CFTR-related conditions. ClinVar contains an entry for this variant (Variation ID: 495885). 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 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Oct 20, 2022	The p.T351I variant (also known as c.1052C>T), located in coding exon 8 of the CFTR gene, results from a C to T substitution at nucleotide position 1052. The threonine at codon 351 is replaced by isoleucine, an amino acid with similar properties. This variant has been seen internally in several individuals who appear to have a non-classic cystic fibrosis phenotype (Ambry internal data). Based on data from gnomAD, the T allele has an overall frequency of 0.001% (4/282554) total alleles studied. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Sep 05, 2021	- -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Oct 10, 2017	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Jul 14, 2023	PP3 -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jun 24, 2024

Variant summary: CFTR c.1052C>T (p.Thr351Ile) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 251162 control chromosomes. To our knowledge, no occurrence of c.1052C>T in individuals affected with Cystic Fibrosis has been reported. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect resulted in approximately 32% of normal chloride channel conductance relative to wild type (e.g., Bihler_2024). The following publication has been ascertained in the context of this evaluation (PMID: 38388235). ClinVar contains an entry for this variant (Variation ID: 495885). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

CFTR-related disorder

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Natera, Inc.

Feb 06, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.87

BayesDel_addAF

Pathogenic

0.33

BayesDel_noAF

Pathogenic

0.42

CADD

Uncertain

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.74

D;.;.;D;.

Eigen

Pathogenic

0.86

Eigen_PC

Pathogenic

0.82

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

0.98

D;D;D;D;D

M_CAP

Pathogenic

0.73

MetaRNN

Pathogenic

0.92

D;D;D;D;D

MetaSVM

Pathogenic

0.91

MutationAssessor

Uncertain

2.9

M;.;.;.;M

PrimateAI

Uncertain

0.74

PROVEAN

Benign

-1.8

N;.;.;N;.

REVEL

Pathogenic

0.90

Sift

Uncertain

0.0010

D;.;.;D;.

Sift4G

Pathogenic

0.0

D;.;.;D;.

Polyphen

1.0

D;.;.;.;.

Vest4

0.95

MutPred

0.69

Gain of helix (P = 0.0696);Gain of helix (P = 0.0696);Gain of helix (P = 0.0696);.;Gain of helix (P = 0.0696);

MVP

1.0

MPC

0.0060

ClinPred

0.94

GERP RS

5.3

Varity_R

0.88

gMVP

0.95

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over