NM_006172.4:c.78T>A

Variant names:

• chr1-11847607-A-T
• rs770401799
• NM_006172.4:c.78T>A

Variant summary

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

The NM_006172.4(NPPA):​c.78T>A​(p.Asn26Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000616 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. 12/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: NPPA NM_006172.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.299

Genes affected

NPPA (HGNC:7939): (natriuretic peptide A) The protein encoded by this gene belongs to the natriuretic peptide family. Natriuretic peptides are implicated in the control of extracellular fluid volume and electrolyte homeostasis. This protein is synthesized as a large precursor (containing a signal peptide), which is processed to release a peptide from the N-terminus with similarity to vasoactive peptide, cardiodilatin, and another peptide from the C-terminus with natriuretic-diuretic activity. Mutations in this gene have been associated with atrial fibrillation familial type 6. This gene is located adjacent to another member of the natriuretic family of peptides on chromosome 1. [provided by RefSeq, Oct 2015]

CLCN6 (HGNC:2024): (chloride voltage-gated channel 6) This gene encodes a member of the voltage-dependent chloride channel protein family. Members of this family can function as either chloride channels or antiporters. This protein is primarily localized to late endosomes and functions as a chloride/proton antiporter. Alternate splicing results in both coding and non-coding variants. Additional alternately spliced variants have been described but their full-length structure is unknown. [provided by RefSeq, Mar 2012]

NPPA-AS1 (HGNC:37635): (NPPA antisense RNA 1)

ENSG00000275915 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NPPA	NM_006172.4	c.78T>A	p.Asn26Lys	missense_variant	Exon 1 of 3	ENST00000376480.7	NP_006163.1
NPPA-AS1	NR_037806.1	n.1653A>T		non_coding_transcript_exon_variant	Exon 4 of 4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NPPA	ENST00000376480.7	c.78T>A	p.Asn26Lys	missense_variant	Exon 1 of 3	1	NM_006172.4	ENSP00000365663.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251494 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135922

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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000264

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461882 Hom.: 0 Cov.: 32 AF XY: 0.00000825 AC XY: 6 AN XY: 727246

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: 0.00000629

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ExAC AF: 0.0000247 AC: 3

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Sep 06, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.78T>A (p.N26K) alteration is located in exon 1 (coding exon 1) of the NPPA gene. This alteration results from a T to A substitution at nucleotide position 78, causing the asparagine (N) at amino acid position 26 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Atrial fibrillation, familial, 6 Uncertain:1

Nov 20, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces asparagine, which is neutral and polar, with lysine, which is basic and polar, at codon 26 of the NPPA protein (p.Asn26Lys). This variant is present in population databases (rs770401799, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with NPPA-related conditions. ClinVar contains an entry for this variant (Variation ID: 240294). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.24
BayesDel_addAF	Benign	-0.22	T
BayesDel_noAF	Benign	-0.55
CADD	Benign	7.7
DANN	Benign	0.96
DEOGEN2	Benign	0.033	.;T
Eigen	Benign	-0.45
Eigen_PC	Benign	-0.57
FATHMM_MKL	Benign	0.32	N
LIST_S2	Benign	0.57	.;T
M_CAP	Benign	0.019	T
MetaRNN	Uncertain	0.47	T;T
MetaSVM	Benign	-0.97	T
PrimateAI	Benign	0.43	T
PROVEAN	Uncertain	-2.4	N;.
REVEL	Benign	0.16
Sift	Uncertain	0.025	D;.
Sift4G	Benign	0.074	T;T
Vest4		0.27
MutPred		0.62		Gain of ubiquitination at N26 (P = 0.0247);Gain of ubiquitination at N26 (P = 0.0247);
MVP		0.80
MPC		0.074
ClinPred		0.71	D
GERP RS		-0.64
gMVP		0.38

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: rs770401799; hg19: chr1-11907664;