rs372452903

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_000171.4(GLRA1):​c.536C>T​(p.Thr179Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,611,416 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T179K) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

GLRA1
NM_000171.4 missense

Scores

7
6
5

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.88

Publications

0 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 2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.891

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GLRA1NM_000171.4 linkc.536C>T p.Thr179Ile missense_variant Exon 5 of 9 ENST00000274576.9 NP_000162.2 P23415-2
GLRA1NM_001146040.2 linkc.536C>T p.Thr179Ile missense_variant Exon 5 of 9 NP_001139512.1 P23415-1
GLRA1NM_001292000.2 linkc.287C>T p.Thr96Ile missense_variant Exon 4 of 8 NP_001278929.1 Q14C71
GLRA1XM_047417105.1 linkc.584C>T p.Thr195Ile 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.536C>T p.Thr179Ile missense_variant Exon 5 of 9 1 NM_000171.4 ENSP00000274576.5 P23415-2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152166
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
251474
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:
0.00000411
AC:
6
AN:
1459250
Hom.:
0
Cov.:
29
AF XY:
0.00000275
AC XY:
2
AN XY:
726032
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33406
American (AMR)
AF:
0.00
AC:
0
AN:
44676
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26100
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39632
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86198
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53252
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000541
AC:
6
AN:
1109992
Other (OTH)
AF:
0.00
AC:
0
AN:
60228
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00211862), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.358
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00000657
AC:
1
AN:
152166
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74344
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41430
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3464
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
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:
0.0000843
Hom.:
0
Bravo
AF:
0.0000113
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Hereditary hyperekplexia Uncertain:1
Sep 20, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 179 of the GLRA1 protein (p.Thr179Ile). This variant is present in population databases (rs372452903, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with GLRA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 464190). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt GLRA1 protein function with a negative predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Uncertain
0.090
CADD
Pathogenic
28
DANN
Uncertain
1.0
Eigen
Pathogenic
0.76
Eigen_PC
Pathogenic
0.73
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.88
D;D
M_CAP
Uncertain
0.16
D
MetaRNN
Pathogenic
0.89
D;D
MetaSVM
Uncertain
0.19
D
MutationAssessor
Benign
1.7
L;L
PhyloP100
7.9
PrimateAI
Pathogenic
0.84
D
PROVEAN
Uncertain
-2.6
D;N
REVEL
Pathogenic
0.70
Sift
Benign
0.14
T;T
Sift4G
Benign
0.41
T;T
Polyphen
1.0
D;D
Vest4
0.82
MVP
0.93
MPC
2.0
ClinPred
0.98
D
GERP RS
4.8
Varity_R
0.42
gMVP
0.67
Mutation Taster
=33/67
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.070
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: rs372452903; hg19: chr5-151235885; API