7-117531068-T-C

Variant names:

• chr7-117531068-T-C
• rs35516286
• NM_000492.4:c.443T>C

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 5P and 6B. PM1 PM5 PP2 BP4_Strong BP6 BS2_Supporting

The NM_000492.4(CFTR):​c.443T>C​(p.Ile148Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00148 in 1,613,710 control chromosomes in the GnomAD database, including 12 homozygotes. In-silico tool predicts a benign 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. I148N) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: 𝑓 0.0010 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0015 (12 hom.)
• Consequence: CFTR NM_000492.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:15
• Conservation: PhyloP100: 7.61
• Publications: 93 publications found

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 Gene-Disease associations (from GenCC):

• cystic fibrosis

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Orphanet
• congenital bilateral absence of vas deferens

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary chronic pancreatitis

  Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 27 uncertain in NM_000492.4
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-117531068-T-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 53949.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 197 curated pathogenic missense variants (we use a threshold of 10). The gene has 46 curated benign missense variants. Gene score misZ: -3.1397 (below the threshold of 3.09). Trascript score misZ: -1.0868 (below the threshold of 3.09). GenCC associations: The gene is linked to hereditary chronic pancreatitis, cystic fibrosis, congenital bilateral absence of vas deferens.
• BP4: Computational evidence support a benign effect (MetaRNN=0.01625809).
• BP6: Variant 7-117531068-T-C is Benign according to our data. Variant chr7-117531068-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 38850.
• BS2: High Homozygotes in GnomAdExome4 at 12 AD,AR geneVariant has number of homozygotes lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000492.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CFTR	NM_000492.4	MANE Select	c.443T>C	p.Ile148Thr	missense	Exon 4 of 27	NP_000483.3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CFTR	ENST00000003084.11	TSL:1 MANE Select	c.443T>C	p.Ile148Thr	missense	Exon 4 of 27	ENSP00000003084.6
	CFTR	ENST00000699602.1		c.443T>C	p.Ile148Thr	missense	Exon 4 of 27	ENSP00000514471.1
	CFTR	ENST00000426809.5	TSL:5	c.443T>C	p.Ile148Thr	missense	Exon 4 of 26	ENSP00000389119.1

Frequencies

GnomAD3 genomes AF: 0.00101 AC: 154 AN: 152140 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000121

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000590

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00498

Gnomad FIN AF: 0.000188

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.00159

Gnomad OTH AF: 0.00239

GnomAD2 exomes AF: 0.00178 AC: 445 AN: 250526 AF XY: 0.00222

Gnomad AFR exome AF: 0.000185

Gnomad AMR exome AF: 0.00148

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000926

Gnomad NFE exome AF: 0.00148

Gnomad OTH exome AF: 0.00164

GnomAD4 exome AF: 0.00153 AC: 2229 AN: 1461452 Hom.: 12 Cov.: 31 AF XY: 0.00173 AC XY: 1260 AN XY: 727004

African (AFR) AF: 0.000239 AC: 8 AN: 33470

American (AMR) AF: 0.00141 AC: 63 AN: 44620

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

South Asian (SAS) AF: 0.00648 AC: 559 AN: 86218

European-Finnish (FIN) AF: 0.000131 AC: 7 AN: 53384

Middle Eastern (MID) AF: 0.00694 AC: 40 AN: 5762

European-Non Finnish (NFE) AF: 0.00131 AC: 1453 AN: 1111820

Other (OTH) AF: 0.00164 AC: 99 AN: 60376

GnomAD4 genome AF: 0.00101 AC: 154 AN: 152258 Hom.: 0 Cov.: 32 AF XY: 0.00117 AC XY: 87 AN XY: 74438

African (AFR) AF: 0.000120 AC: 5 AN: 41564

American (AMR) AF: 0.000589 AC: 9 AN: 15282

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00499 AC: 24 AN: 4814

European-Finnish (FIN) AF: 0.000188 AC: 2 AN: 10624

Middle Eastern (MID) AF: 0.00340 AC: 1 AN: 294

European-Non Finnish (NFE) AF: 0.00159 AC: 108 AN: 68002

Other (OTH) AF: 0.00236 AC: 5 AN: 2116

Alfa AF: 0.00155 Hom.: 3

Bravo AF: 0.00117

TwinsUK AF: 0.00135 AC: 5

ALSPAC AF: 0.00130 AC: 5

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000814 AC: 7

ExAC AF: 0.00185 AC: 224

Asia WGS AF: 0.000577 AC: 2 AN: 3478

EpiCase AF: 0.00229

EpiControl AF: 0.00136

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:15

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Cystic fibrosis Uncertain:2 Benign:9

Aug 06, 2019

Natera, Inc.

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

Jun 25, 2019

Johns Hopkins Genomics, Johns Hopkins University

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Apr 14, 2017

Counsyl

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com.

Apr 30, 2024

SIB Swiss Institute of Bioinformatics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: curation

This variant is interpreted as a likely benign, for Cystic fibrosis, in Autosomal Recessive manner. The following ACMG Tag(s) were applied: BS2 => Observed in a healthy adult individual for a recessive (homozygous), dominant (heterozygous), or X-linked (hemizygous) disorder, with full penetrance expected at an early age. BP2 => Observed in trans with a pathogenic variant for a fully penetrant dominant gene/disorder or observed in cis with a pathogenic variant in any inheritance pattern (PMID:12394343).

Sep 05, 2022

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: curation

This variant was identified in 2 unrelated patients with a clinically confirmed diagnosis of cystic fibrosis. The variant was classified in the context of a project re-classifying variants in the German Cystic Fibrosis Registry (Muko.e.V.). Link: https://www.muko.info/angebote/qualitaetsmanagement/register/cf-einrichtungen/mukoweb. Criteria applied: PM5, PP4, BS2, BS3, BP2

Mar 13, 2015

Ambry Genetics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Aug 22, 2023

Mendelics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Jan 29, 2018

CFTR-France

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: curation

the variant does not result in CFTR-RD neither

Feb 19, 2025

3billion

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The variant is observed at an extremely low frequency in the gnomAD v4.1.0 dataset (total allele frequency: 0.148%). Predicted Consequence/Location: Missense variant In silico tool predictions suggest damaging effect of the variant on gene or gene product [3Cnet: 0.73 (>=0.6, sensitivity 0.72 and precision 0.9)]. A different missense change at the same codon (p.Ile148Asn) has been reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000053949 /PMID: 15480987). The variant has been reported at least twice as benign with clinical assertions and evidence for the classification (ClinVar ID: VCV000038850). Therefore, this variant is classified as VUS according to the recommendation of ACMG/AMP guideline.

Jan 27, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Jun 10, 2021

Genome-Nilou Lab

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

not specified Benign:3

PreventionGenetics, part of Exact Sciences

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Aug 06, 2012

Eurofins Ntd Llc (ga)

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Dec 24, 2019

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

not provided Benign:3

Nov 19, 2024

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Feb 23, 2021

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 1284534, 23974870, 9305991, 12394343, 10653141, 11484207, 22658665, 22975760, 20021716, 15287992, 26990548, 7517268, 15017334, 18456578, 18685558, 16822950, 11242048, 19491324, 15371902)

Aug 01, 2025

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

CFTR: PM5, BS2

CFTR-related disorder Uncertain:1

Mar 06, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.12	T
BayesDel_noAF	Uncertain	0.050
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.48	T
Eigen	Uncertain	0.22
Eigen_PC	Uncertain	0.39
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.47	D
MetaRNN	Benign	0.016	T
MetaSVM	Uncertain	0.20	D
MutationAssessor	Benign	0.69	N
PhyloP100		7.6
PrimateAI	Uncertain	0.52	T
PROVEAN	Benign	-0.68	N
REVEL	Uncertain	0.57
Sift	Benign	0.35	T
Sift4G	Uncertain	0.0020	D
Polyphen		0.29	B
Vest4		0.82
MVP		1.0
MPC		0.0038
ClinPred		0.044	T
GERP RS		5.7
Varity_R		0.45
gMVP		0.91
Mutation Taster		=9/91	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs35516286; hg19: chr7-117171122;