chr7-117535264-A-G

Variant names:

• chr7-117535264-A-G
• rs397508764
• NM_000492.4:c.596A>G

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Very_Strong

The NM_000492.4(CFTR):​c.596A>G​(p.His199Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,858 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H199Y) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CFTR NM_000492.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3 O:1
• Conservation: PhyloP100: 6.93
• Publications: 10 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: Pathogenic. The variant received 19 ACMG points.

• PM1: In a hotspot region, there are 12 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 27 uncertain in NM_000492.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-117535263-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 54018.Status of the report is reviewed_by_expert_panel, 3 stars.
• 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984
• PP5: Variant 7-117535264-A-G is Pathogenic according to our data. Variant chr7-117535264-A-G is described in ClinVar as Pathogenic. ClinVar VariationId is 54019.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CFTR	NM_000492.4	c.596A>G	p.His199Arg	missense_variant	Exon 6 of 27	ENST00000003084.11	NP_000483.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CFTR	ENST00000003084.11	c.596A>G	p.His199Arg	missense_variant	Exon 6 of 27	1	NM_000492.4	ENSP00000003084.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251450 AF XY: 0.00000736

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461858 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727232

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111988

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Cystic fibrosis Pathogenic:2 Other:1

ClinVar Staff, National Center for Biotechnology Information (NCBI)

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Jul 15, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.His199 amino acid residue in CFTR. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 7525450, 9439669, 23974870, 27143075, 28608624). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. ClinVar contains an entry for this variant (Variation ID: 54019). This missense change has been observed in individual(s) with cystic fibrosis (PMID: 12865275, 15084222). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is present in population databases (rs397508764, gnomAD 0.0009%). This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 199 of the CFTR protein (p.His199Arg).

Jan 29, 2018

CFTR-France

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

CFTR-related disorder Pathogenic:1

Dec 06, 2017

Natera, Inc.

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D;.;.;D;.
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D;D;D;D;D
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D
MetaSVM	Pathogenic	0.85	D
MutationAssessor	Pathogenic	2.9	M;.;.;.;M
PhyloP100		6.9
PrimateAI	Uncertain	0.78	T
PROVEAN	Uncertain	-3.9	D;.;.;D;.
REVEL	Pathogenic	0.88
Sift	Benign	0.050	D;.;.;D;.
Sift4G	Pathogenic	0.0	D;.;.;D;.
Vest4		0.99
ClinPred		0.99	D
GERP RS		5.5
Varity_R		0.96
gMVP		0.97
Mutation Taster		=8/92	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs397508764; hg19: chr7-117175318;