rs121918414

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PP3_StrongPP5

The NM_000171.4(GLRA1):​c.523A>G​(p.Met175Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000248 in 1,612,042 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M175I) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000026 ( 0 hom. )

Consequence

GLRA1
NM_000171.4 missense

Scores

10
7
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:1

Conservation

PhyloP100: 7.81

Publications

3 publications found
Variant links:
Genes affected
GLRA1 (HGNC:4326): (glycine receptor alpha 1) The protein encoded by this gene is a subunit of a pentameric inhibitory glycine receptor, which mediates postsynaptic inhibition in the central nervous system. Defects in this gene are a cause of startle disease (STHE), also known as hereditary hyperekplexia or congenital stiff-person syndrome. Multiple transcript variants encoding different isoforms have been found. [provided by RefSeq, Dec 2015]
GLRA1 Gene-Disease associations (from GenCC):
  • hyperekplexia 1
    Inheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • hereditary hyperekplexia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.979
PP5
Variant 5-151856337-T-C is Pathogenic according to our data. Variant chr5-151856337-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 16068.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GLRA1NM_000171.4 linkc.523A>G p.Met175Val missense_variant Exon 5 of 9 ENST00000274576.9 NP_000162.2 P23415-2
GLRA1NM_001146040.2 linkc.523A>G p.Met175Val missense_variant Exon 5 of 9 NP_001139512.1 P23415-1
GLRA1NM_001292000.2 linkc.274A>G p.Met92Val missense_variant Exon 4 of 8 NP_001278929.1 Q14C71
GLRA1XM_047417105.1 linkc.571A>G p.Met191Val missense_variant Exon 5 of 9 XP_047273061.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GLRA1ENST00000274576.9 linkc.523A>G p.Met175Val missense_variant Exon 5 of 9 1 NM_000171.4 ENSP00000274576.5 P23415-2

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152094
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251464
AF XY:
0.00000736
show subpopulations
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000260
AC:
38
AN:
1459948
Hom.:
0
Cov.:
29
AF XY:
0.0000207
AC XY:
15
AN XY:
726364
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33432
American (AMR)
AF:
0.00
AC:
0
AN:
44684
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26088
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39640
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86218
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53258
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000324
AC:
36
AN:
1110610
Other (OTH)
AF:
0.0000332
AC:
2
AN:
60250
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.461
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
4
8
12
16
20
<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:
0.0000131
AC:
2
AN:
152094
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74288
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41414
American (AMR)
AF:
0.00
AC:
0
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
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:
0.00000502
Hom.:
0
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Hyperekplexia 1 Pathogenic:1Uncertain:1
Feb 24, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 01, 2001
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Hereditary hyperekplexia Pathogenic:1
Jan 30, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 175 of the GLRA1 protein (p.Met175Val). This variant is present in population databases (rs121918414, gnomAD 0.0009%). This missense change has been observed in individual(s) with autosomal recessive hyperekplexia (PMID: 11702206). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is also known as M147V (A830G). ClinVar contains an entry for this variant (Variation ID: 16068). 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 GLRA1 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change does not substantially affect GLRA1 function (PMID: 11702206). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.76
BayesDel_addAF
Pathogenic
0.40
D
BayesDel_noAF
Pathogenic
0.34
CADD
Pathogenic
26
DANN
Uncertain
0.99
Eigen
Pathogenic
0.88
Eigen_PC
Pathogenic
0.78
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Uncertain
0.24
D
MetaRNN
Pathogenic
0.98
D;D
MetaSVM
Uncertain
0.75
D
MutationAssessor
Pathogenic
3.2
M;M
PhyloP100
7.8
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-3.5
D;D
REVEL
Pathogenic
0.92
Sift
Uncertain
0.0010
D;D
Sift4G
Uncertain
0.0040
D;D
Polyphen
0.98
D;D
Vest4
0.89
MutPred
0.93
Loss of methylation at K171 (P = 0.1628);Loss of methylation at K171 (P = 0.1628);
MVP
0.83
MPC
2.1
ClinPred
0.99
D
GERP RS
4.8
Varity_R
0.91
gMVP
0.82
Mutation Taster
=5/95
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
Splicevardb
2.0
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs121918414; hg19: chr5-151235898; API