rs1060503175

chr2-49922116-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_001330078.2(NRXN1):c.4352C>T(p.Ala1451Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. A1451G) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NRXN1 NM_001330078.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 10.0

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NRXN1	NM_001330078.2	c.4352C>T	p.Ala1451Val	missense_variant	23/23	ENST00000401669.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NRXN1	ENST00000401669.7	c.4352C>T	p.Ala1451Val	missense_variant	23/23	5	NM_001330078.2	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

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

Invitae

Nov 10, 2016

In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a NRXN1-related disease. This sequence change replaces alanine with valine at codon 1491 of the NRXN1 protein (p.Ala1491Val). The alanine residue is highly conserved and there is a small physicochemical difference between alanine and valine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.25
Cadd	Pathogenic	26
Dann	Uncertain	1.0
Eigen	Uncertain	0.60
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Benign	0.037	D
MetaRNN	Uncertain	0.57	D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.46	T
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.86	D
Sift4G	Pathogenic	0.0	D;D;.;D;D;D;D;D;D;D;D;D;D;D
Polyphen		0.93	.;.;.;.;P;.;.;.;.;.;.;.;.;.
Vest4		0.80
MutPred		0.24		.;Loss of helix (P = 0.0558);.;.;.;.;.;.;.;.;.;.;.;.;
MVP		0.40
MPC		1.5
ClinPred		0.97	D
GERP RS		5.4
Varity_R		0.23
gMVP		0.93

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: rs1060503175; hg19: chr2-50149254;