13-101055386-G-A

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP2BP4_Strong

The NM_052867.4(NALCN):c.5126C>T(p.Ala1709Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000743 in 1,614,000 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

NALCN
NM_052867.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 4.21

Variant links:

Genes affected

NALCN (HGNC:19082): (sodium leak channel, non-selective) This gene encodes a voltage-independent, nonselective cation channel which belongs to a family of voltage-gated sodium and calcium channels that regulates the resting membrane potential and excitability of neurons. This family is expressed throughout the nervous system and conducts a persistent sodium leak current that contributes to tonic neuronal excitability. The encoded protein forms a channelosome complex that includes G-protein-coupled receptors, UNC-79, UNC-80, NCA localization factor-1, and src family tyrosine kinases. Naturally occurring mutations in this gene are associated with infantile neuroaxonal dystrophy, infantile hypotonia with psychomotor retardation and characteristic facies (IHPRF) syndrome, and congenital contractures of the limbs and face with hypotonia and developmental delay (CLIFAHDD) syndrome. A knockout of the orthologous gene in mice results in paralysis with a severely disrupted respiratory rhythm, and lethality within 24 hours after birth. [provided by RefSeq, Apr 2017]

NALCN links:

NALCN-AS1 (HGNC:42743): (NALCN antisense RNA 1)

NALCN-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP2

Missense variant in the NALCN gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 63 curated pathogenic missense variants (we use a threshold of 10). The gene has 9 curated benign missense variants. Gene score misZ: 4.9555 (above the threshold of 3.09). Trascript score misZ: 6.7536 (above the threshold of 3.09). GenCC associations: The gene is linked to hypotonia, infantile, with psychomotor retardation and characteristic facies 1, digitotalar dysmorphism, hypotonia, infantile, with psychomotor retardation and characteristic facies, congenital contractures of the limbs and face, hypotonia, and developmental delay, Freeman-Sheldon syndrome, Sheldon-hall syndrome.

BP4

Computational evidence support a benign effect (MetaRNN=0.057310402).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NALCN	NM_052867.4 link	c.5126C>T	p.Ala1709Val	missense_variant	Exon 44 of 44	ENST00000251127.11	NP_443099.1	Q8IZF0-1A0A024RE05

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NALCN	ENST00000251127.11 link	c.5126C>T	p.Ala1709Val	missense_variant	Exon 44 of 44	1	NM_052867.4	ENSP00000251127.6		Q8IZF0-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152152

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251422

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135880

show subpopulations

Gnomad AFR exome

AF:

0.0000615

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000684

AC:

AN:

1461848

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727224

show subpopulations

Gnomad4 AFR exome

AF:

0.000119

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:

0.00000540

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152152

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74340

show subpopulations

Gnomad4 AFR

AF:

0.0000483

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Oct 14, 2020

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.5126C>T (p.A1709V) alteration is located in exon 44 (coding exon 43) of the NALCN gene. This alteration results from a C to T substitution at nucleotide position 5126, causing the alanine (A) at amino acid position 1709 to be replaced by a valine (V). Based on data from the Genome Aggregation Database (gnomAD) database, the NALCN c.5126C>T alteration was observed in 0.0007% (2/282822) of total alleles studied, with a frequency of 0.008% (2/24964) in the African subpopulation. This amino acid position is poorly conserved in available vertebrate species. The p.A1709V alteration is predicted to be tolerated by in silico analysis. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Sep 17, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1709 of the NALCN protein (p.Ala1709Val). This variant is present in population databases (rs373221131, gnomAD 0.008%). This variant has not been reported in the literature in individuals affected with NALCN-related conditions. ClinVar contains an entry for this variant (Variation ID: 2227836). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt NALCN protein function with a negative predictive value of 80%. 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

0.076

BayesDel_addAF

Benign

-0.13

BayesDel_noAF

Benign

-0.24

CADD

Benign

DANN

Benign

0.93

DEOGEN2

Benign

0.13

Eigen

Benign

-0.60

Eigen_PC

Benign

-0.43

FATHMM_MKL

Uncertain

0.87

LIST_S2

Benign

0.81

M_CAP

Benign

0.044

MetaRNN

Benign

0.057

MetaSVM

Uncertain

0.17

MutationAssessor

Benign

0.0

PrimateAI

Benign

0.33

PROVEAN

Benign

-0.35

REVEL

Benign

0.25

Sift

Benign

0.44

Sift4G

Benign

0.31

Polyphen

0.091

Vest4

0.031

MutPred

0.32

Gain of catalytic residue at D1708 (P = 0);

MVP

0.37

MPC

0.44

ClinPred

0.14

GERP RS

4.6

Varity_R

0.034

gMVP

0.53

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over