chr5-151822686-A-G

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_000171.4(GLRA1):​c.1337T>C​(p.Val446Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,612,250 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. V446I) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

GLRA1
NM_000171.4 missense

Scores

7
11

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.11

Publications

1 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 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.3583579).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GLRA1NM_000171.4 linkc.1337T>C p.Val446Ala missense_variant Exon 9 of 9 ENST00000274576.9 NP_000162.2 P23415-2
GLRA1NM_001146040.2 linkc.1361T>C p.Val454Ala missense_variant Exon 9 of 9 NP_001139512.1 P23415-1
GLRA1NM_001292000.2 linkc.1088T>C p.Val363Ala missense_variant Exon 8 of 8 NP_001278929.1 Q14C71
GLRA1XM_047417105.1 linkc.1385T>C p.Val462Ala missense_variant Exon 9 of 9 XP_047273061.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GLRA1ENST00000274576.9 linkc.1337T>C p.Val446Ala missense_variant Exon 9 of 9 1 NM_000171.4 ENSP00000274576.5 P23415-2
GLRA1ENST00000455880.2 linkc.1361T>C p.Val454Ala missense_variant Exon 9 of 9 1 ENSP00000411593.2 P23415-1
GLRA1ENST00000462581.6 linkn.*1095T>C non_coding_transcript_exon_variant Exon 8 of 8 1 ENSP00000430595.1 E5RJ70
GLRA1ENST00000462581.6 linkn.*1095T>C 3_prime_UTR_variant Exon 8 of 8 1 ENSP00000430595.1 E5RJ70

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152072
Hom.:
0
Cov.:
31
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:
251256
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:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460178
Hom.:
0
Cov.:
30
AF XY:
0.00000138
AC XY:
1
AN XY:
726570
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33432
American (AMR)
AF:
0.00
AC:
0
AN:
44708
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26116
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39688
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86210
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53412
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5756
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1110504
Other (OTH)
AF:
0.00
AC:
0
AN:
60352
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

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:
0.00000658
AC:
1
AN:
152072
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74272
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41392
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10590
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
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
ExAC
AF:
0.00000824
AC:
1

ClinVar

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

Submissions by phenotype

Hereditary hyperekplexia Uncertain:1
Jan 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 446 of the GLRA1 protein (p.Val446Ala). This variant is present in population databases (rs774573940, gnomAD 0.0009%). 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: 1958927). 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 not expected to disrupt GLRA1 protein function with a negative predictive value of 95%. 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
0.12
BayesDel_addAF
Uncertain
0.042
T
BayesDel_noAF
Benign
-0.18
CADD
Pathogenic
26
DANN
Uncertain
1.0
Eigen
Benign
0.19
Eigen_PC
Uncertain
0.32
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Benign
0.85
D;D
M_CAP
Benign
0.036
D
MetaRNN
Benign
0.36
T;T
MetaSVM
Benign
-0.50
T
MutationAssessor
Benign
0.59
.;N
PhyloP100
9.1
PrimateAI
Uncertain
0.67
T
PROVEAN
Benign
-1.3
N;N
REVEL
Benign
0.28
Sift
Uncertain
0.0040
D;D
Sift4G
Uncertain
0.021
D;D
Polyphen
0.57
P;B
Vest4
0.55
MutPred
0.41
.;Loss of stability (P = 0.0322);
MVP
0.80
MPC
0.090
ClinPred
0.84
D
GERP RS
4.7
Varity_R
0.20
gMVP
0.84
Mutation Taster
=36/64
disease causing

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

Other links and lift over

dbSNP: rs774573940; hg19: chr5-151202247; API