7-117509047-G-C

Variant names:

• chr7-117509047-G-C
• rs77284892
• NM_000492.4:c.178G>C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PM5

The NM_000492.4(CFTR):​c.178G>C​(p.Glu60Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000275 in 1,456,618 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E60K) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: CFTR NM_000492.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.71

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a helix (size 17) in uniprot entity CFTR_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) 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 chr7-117509047-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CFTR	NM_000492.4	c.178G>C	p.Glu60Gln	missense_variant	Exon 3 of 27	ENST00000003084.11	NP_000483.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CFTR	ENST00000003084.11	c.178G>C	p.Glu60Gln	missense_variant	Exon 3 of 27	1	NM_000492.4	ENSP00000003084.6

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000275 AC: 4 AN: 1456618 Hom.: 0 Cov.: 29 AF XY: 0.00000414 AC XY: 3 AN XY: 725060

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000361

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cystic fibrosis Uncertain:1

Oct 24, 2019

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.E60Q variant (also known as c.178G>C), located in coding exon 3 of the CFTR gene, results from a G to C substitution at nucleotide position 178. The glutamic acid at codon 60 is replaced by glutamine, an amino acid with highly similar properties. This amino acid position is highly 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.77
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.060
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.54	D;.;.;T;.
Eigen	Pathogenic	0.80
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D;D;D;D;D
M_CAP	Pathogenic	0.54	D
MetaRNN	Uncertain	0.72	D;D;D;D;D
MetaSVM	Pathogenic	0.85	D
MutationAssessor	Benign	1.9	L;.;.;.;L
PrimateAI	Uncertain	0.60	T
PROVEAN	Benign	-1.3	N;.;.;N;.
REVEL	Uncertain	0.57
Sift	Benign	0.13	T;.;.;T;.
Sift4G	Pathogenic	0.0	D;.;.;D;.
Polyphen		1.0	D;.;.;.;.
Vest4		0.75
MutPred		0.40		Gain of MoRF binding (P = 0.0289);Gain of MoRF binding (P = 0.0289);Gain of MoRF binding (P = 0.0289);Gain of MoRF binding (P = 0.0289);Gain of MoRF binding (P = 0.0289);
MVP		1.0
MPC		0.0068
ClinPred		0.94	D
GERP RS		5.7
Varity_R		0.49
gMVP		0.92

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

Other links and lift over

dbSNP: rs77284892; hg19: chr7-117149101; COSMIC: COSV99069638; COSMIC: COSV99069638;