rs774230140

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM4

The NM_001330078.2(NRXN1):​c.665_673dupAGGGCGAGG​(p.Glu222_Glu224dup) variant causes a conservative inframe insertion change. The variant allele was found at a frequency of 0.0000187 in 1,601,738 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. G225G) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

NRXN1
NM_001330078.2 conservative_inframe_insertion

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 3.97

Publications

0 publications found
Variant links:
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]
NRXN1 Gene-Disease associations (from GenCC):
  • complex neurodevelopmental disorder
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • chromosome 2p16.3 deletion syndrome
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • Pitt-Hopkins-like syndrome 2
    Inheritance: AR Classification: STRONG, MODERATE Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • autism
    Inheritance: AD Classification: MODERATE Submitted by: G2P
  • schizophrenia
    Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM4
Nonframeshift variant in NON repetitive region in NM_001330078.2.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NRXN1NM_001330078.2 linkc.665_673dupAGGGCGAGG p.Glu222_Glu224dup conservative_inframe_insertion Exon 2 of 23 ENST00000401669.7 NP_001317007.1 E7ERL8

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NRXN1ENST00000401669.7 linkc.665_673dupAGGGCGAGG p.Glu222_Glu224dup conservative_inframe_insertion Exon 2 of 23 5 NM_001330078.2 ENSP00000385017.2 E7ERL8

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152180
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000404
AC:
9
AN:
222698
AF XY:
0.0000493
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000245
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000183
GnomAD4 exome
AF:
0.0000179
AC:
26
AN:
1449442
Hom.:
0
Cov.:
31
AF XY:
0.0000208
AC XY:
15
AN XY:
719820
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33162
American (AMR)
AF:
0.000323
AC:
14
AN:
43404
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25790
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38956
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84532
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51642
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5732
European-Non Finnish (NFE)
AF:
0.00000994
AC:
11
AN:
1106398
Other (OTH)
AF:
0.0000167
AC:
1
AN:
59826
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.452
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152296
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74460
show subpopulations
African (AFR)
AF:
0.0000240
AC:
1
AN:
41594
American (AMR)
AF:
0.000131
AC:
2
AN:
15308
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5134
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68008
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
May 20, 2019
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 26, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In-frame duplication of 3 amino acids in a non-repeat region; Has not been previously published as pathogenic or benign to our knowledge -

Inborn genetic diseases Uncertain:1
Aug 04, 2016
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.665_673dupAGGGCGAGG variant (also known as p.E222_E224dup), located in coding exon 1 of the NRXN1 gene, results from an in-frame duplication of AGGGCGAGG at nucleotide positions 665 to 673. This results in the duplication of 3 extra residues (EGE) between codons 222 and 224. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6334 samples (12668 alleles) with coverage at this position. This amino acid positions are not well conserved in available vertebrate species. Since supporting evidence is limited at this time, the clinical significance of this variant remains unclear. -

Pitt-Hopkins-like syndrome 2 Uncertain:1
Jan 22, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant, c.665_673dup, results in the insertion of 3 amino acid(s) of the NRXN1 protein (p.Glu222_Glu224dup), but otherwise preserves the integrity of the reading frame. This variant is present in population databases (rs774230140, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with NRXN1-related conditions. ClinVar contains an entry for this variant (Variation ID: 539879). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -

Pitt-Hopkins-like syndrome 2;C3808494:Chromosome 2p16.3 deletion syndrome Uncertain:1
-
Center for Genomics, Ann and Robert H. Lurie Children's Hospital of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

NRXN1 NM_001135659.2 exon 2 p.Glu222_Glu224dup (c.665_673dup): This variant has not been reported in the literature but is present in 9/32736 Latino alleles in the Genome Aggregation Database (http://gnomad.broadinstitute.org/rs774230140). Evolutionary conservation and computational predictive tools for this variant are limited or unavailable. This variant represents an in-frame duplication of 3 amino acids at position 222 and is not predicted to alter the reading frame. However, the effect of this variant on the protein is unclear. In summary, data on this variant is insufficient for disease classification. Therefore, the clinical significance of this variant is uncertain -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
4.0
Mutation Taster
=65/35
polymorphism

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs774230140; hg19: chr2-51254738; API