2-51028124-G-C

Position:

• chr2-51028124-G-C

Variant summary

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

The NM_001330078.2(NRXN1):​c.150C>G​(p.Cys50Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000706 in 1,416,128 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. C50C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 7.1e-7 (0 hom.)
• Consequence: NRXN1 NM_001330078.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.0650

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.150C>G	p.Cys50Trp	missense_variant	2/23	ENST00000401669.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NRXN1	ENST00000401669.7	c.150C>G	p.Cys50Trp	missense_variant	2/23	5	NM_001330078.2	A1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 7.06e-7 AC: 1 AN: 1416128 Hom.: 0 Cov.: 31 AF XY: 0.00000143 AC XY: 1 AN XY: 700360

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: 9.16e-7

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

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Dec 07, 2016

A variant of uncertain significance has been identified in the NRXN1 gene. The C50W variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. The C50W variant is not observed in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). The C50W variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species and in silico analysis predicts this variant is probably damaging to the protein structure/function. However, missense variants in nearby residues have not been reported in Human Gene Mutation Database in association with NRXN1-related disorders (Stenson et al., 2014). Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.25
CADD	Benign	23
DANN	Uncertain	0.99
Eigen	Benign	0.13
Eigen_PC	Benign	0.070
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.10	D
MetaRNN	Uncertain	0.73	D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.077	T
MutationAssessor	Uncertain	2.5	M;M;M;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.90	D
Sift4G	Benign	0.071	T;T;T;T;T;T;T;D;.;D
Polyphen		0.55, 1.0	.;P;D;.;.;.;.;.;.;.
Vest4		0.90
MutPred		0.43		Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);Loss of catalytic residue at S52 (P = 0.0666);
MVP		0.83
MPC		0.84
ClinPred		0.68	D
GERP RS		1.7
Varity_R		0.14
gMVP		0.96

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: rs1057518563; hg19: chr2-51255262;