Menu
GeneBe

rs773790621

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1PM2

The NM_000492.4(CFTR):ā€‹c.766A>Gā€‹(p.Ser256Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000256 in 1,599,070 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (ā˜…ā˜…). Synonymous variant affecting the same amino acid position (i.e. S256S) has been classified as Likely benign.

Frequency

Genomes: š‘“ 0.0000066 ( 0 hom., cov: 32)
Exomes š‘“: 0.000028 ( 0 hom. )

Consequence

CFTR
NM_000492.4 missense

Scores

1
9
9

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 8.79
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000492.4
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
CFTRNM_000492.4 linkuse as main transcriptc.766A>G p.Ser256Gly missense_variant 7/27 ENST00000003084.11

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
CFTRENST00000003084.11 linkuse as main transcriptc.766A>G p.Ser256Gly missense_variant 7/271 NM_000492.4 P2P13569-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152220
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000520
AC:
12
AN:
230864
Hom.:
0
AF XY:
0.0000803
AC XY:
10
AN XY:
124456
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.000417
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000276
AC:
40
AN:
1446850
Hom.:
0
Cov.:
31
AF XY:
0.0000376
AC XY:
27
AN XY:
718730
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000461
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
9.06e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152220
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74364
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000207
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378
ExAC
AF:
0.0000495
AC:
6

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cystic fibrosis Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingInvitaeMay 14, 2022This sequence change replaces serine, which is neutral and polar, with glycine, which is neutral and non-polar, at codon 256 of the CFTR protein (p.Ser256Gly). This variant is present in population databases (rs773790621, gnomAD 0.04%). 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: 582520). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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. -
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsMay 04, 2023The p.S256G variant (also known as c.766A>G), located in coding exon 7 of the CFTR gene, results from an A to G substitution at nucleotide position 766. The serine at codon 256 is replaced by glycine, an amino acid with similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
CFTR-related disorder Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Sep 08, 2017- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.12
T
BayesDel_noAF
Benign
-0.090
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.64
D;.;.;T;.
Eigen
Benign
-0.0059
Eigen_PC
Benign
0.21
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Uncertain
0.89
D;D;D;D;D
M_CAP
Uncertain
0.099
D
MetaRNN
Uncertain
0.49
T;T;T;T;T
MetaSVM
Uncertain
-0.20
T
MutationAssessor
Benign
0.69
N;.;.;.;N
MutationTaster
Benign
0.95
N;N
PrimateAI
Benign
0.36
T
PROVEAN
Benign
-0.98
N;.;.;N;.
REVEL
Uncertain
0.49
Sift
Uncertain
0.011
D;.;.;D;.
Sift4G
Uncertain
0.0030
D;.;.;D;.
Polyphen
0.0050
B;.;.;.;.
Vest4
0.43
MutPred
0.81
Loss of phosphorylation at S256 (P = 0.0504);Loss of phosphorylation at S256 (P = 0.0504);Loss of phosphorylation at S256 (P = 0.0504);.;Loss of phosphorylation at S256 (P = 0.0504);
MVP
0.99
MPC
0.0045
ClinPred
0.23
T
GERP RS
5.1
Varity_R
0.56
gMVP
0.80

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.

Other links and lift over

dbSNP: rs773790621; hg19: chr7-117176624; API