2-49922131-A-T

Position:

• chr2-49922131-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001330078.2(NRXN1):​c.4337T>A​(p.Leu1446His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,884 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 Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: NRXN1 NM_001330078.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.32

Genes affected

NRXN1 (HGNC:8008): (neurexin 1) This gene encodes a single-pass type I membrane protein that belongs to the neurexin family. Neurexins are cell-surface receptors that bind neuroligins to form Ca(2+)-dependent neurexin/neuroligin complexes at synapses in the central nervous system. This complex is required for efficient neurotransmission and is involved in the formation of synaptic contacts. Three members of this gene family have been studied in detail and are estimated to generate over 3,000 variants through the use of two alternative promoters (alpha and beta) and extensive alternative splicing in each family member. Recently, a third promoter (gamma) was identified for this gene in the 3' region. Mutations in this gene are associated with Pitt-Hopkins-like syndrome-2 and may contribute to susceptibility to schizophrenia. [provided by RefSeq, Aug 2016]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.81

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NRXN1	NM_001330078.2	c.4337T>A	p.Leu1446His	missense_variant	23/23	ENST00000401669.7	NP_001317007.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NRXN1	ENST00000401669.7	c.4337T>A	p.Leu1446His	missense_variant	23/23	5	NM_001330078.2	ENSP00000385017	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251304 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135806

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: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461884 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000468 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Pitt-Hopkins-like syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 04, 2023

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. 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 NRXN1 protein function. ClinVar contains an entry for this variant (Variation ID: 539873). This variant has not been reported in the literature in individuals affected with NRXN1-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.0009%). This sequence change replaces leucine, which is neutral and non-polar, with histidine, which is basic and polar, at codon 1486 of the NRXN1 protein (p.Leu1486His). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.35
CADD	Pathogenic	31
DANN	Uncertain	0.98
DEOGEN2	Benign	0.18	.;T;T;.;.;.;T;.;.;.;.;.;T;.
Eigen	Uncertain	0.62
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.20	D
MetaRNN	Pathogenic	0.81	D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.061	D
MutationAssessor	Uncertain	2.2	.;.;.;.;.;M;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-4.6	.;D;.;N;D;D;.;.;.;D;.;.;.;.
REVEL	Pathogenic	0.76
Sift	Pathogenic	0.0	.;D;.;D;D;D;.;.;.;D;.;.;.;.
Sift4G	Pathogenic	0.0	D;D;.;D;D;D;D;D;D;D;D;D;D;D
Polyphen		1.0	.;.;.;.;D;.;.;.;.;.;.;.;.;.
Vest4		0.81
MutPred		0.47		.;Loss of stability (P = 0.0143);.;.;.;.;.;.;.;.;.;.;.;.;
MVP		0.55
MPC		2.1
ClinPred		0.99	D
GERP RS		6.0
Varity_R		0.78
gMVP		0.97

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: rs1293864569; hg19: chr2-50149269;