rs77655188

Variant summary

Our verdict is Benign. Variant got -14 ACMG points: 2P and 16B. PP2PP3BP6_Very_StrongBS1BS2

The NM_000817.3(GAD1):​c.80C>A​(p.Thr27Lys) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000272 in 1,614,022 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00029 ( 0 hom., cov: 31)
Exomes 𝑓: 0.00027 ( 3 hom. )

Consequence

GAD1
NM_000817.3 missense, splice_region

Scores

2
9
8
Splicing: ADA: 0.9675
2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts U:1B:2

Conservation

PhyloP100: 5.21
Variant links:
Genes affected
GAD1 (HGNC:4092): (glutamate decarboxylase 1) This gene encodes one of several forms of glutamic acid decarboxylase, identified as a major autoantigen in insulin-dependent diabetes. The enzyme encoded is responsible for catalyzing the production of gamma-aminobutyric acid from L-glutamic acid. A pathogenic role for this enzyme has been identified in the human pancreas since it has been identified as an autoantigen and an autoreactive T cell target in insulin-dependent diabetes. This gene may also play a role in the stiff man syndrome. Deficiency in this enzyme has been shown to lead to pyridoxine dependency with seizures. Alternative splicing of this gene results in two products, the predominant 67-kD form and a less-frequent 25-kD form. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -14 ACMG points.

PP2
Missense variant in gene, where missense usually causes diseases (based on misZ statistic), GAD1. . Gene score misZ 2.3151 (greater than the threshold 3.09). Trascript score misZ 3.7409 (greater than threshold 3.09). GenCC has associacion of gene with cerebral palsy, spastic quadriplegic, 1, developmental and epileptic encephalopathy 89, early infantile epileptic encephalopathy, spastic quadriplegic cerebral palsy, neurodevelopmental disorder with progressive spasticity and brain white matter abnormalities.
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.
BP6
Variant 2-170818671-C-A is Benign according to our data. Variant chr2-170818671-C-A is described in ClinVar as [Likely_benign]. Clinvar id is 560641.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.000289 (44/152324) while in subpopulation EAS AF= 0.00791 (41/5186). AF 95% confidence interval is 0.00599. There are 0 homozygotes in gnomad4. There are 23 alleles in male gnomad4 subpopulation. Median coverage is 31. This position pass quality control queck.
BS2
High Homozygotes in GnomAdExome4 at 3 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GAD1NM_000817.3 linkuse as main transcriptc.80C>A p.Thr27Lys missense_variant, splice_region_variant 2/17 ENST00000358196.8 NP_000808.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GAD1ENST00000358196.8 linkuse as main transcriptc.80C>A p.Thr27Lys missense_variant, splice_region_variant 2/171 NM_000817.3 ENSP00000350928 P1Q99259-1

Frequencies

GnomAD3 genomes
AF:
0.000289
AC:
44
AN:
152206
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00789
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000765
AC:
192
AN:
251036
Hom.:
1
AF XY:
0.000707
AC XY:
96
AN XY:
135736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000665
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00854
Gnomad SAS exome
AF:
0.000229
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000265
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.000270
AC:
395
AN:
1461698
Hom.:
3
Cov.:
30
AF XY:
0.000238
AC XY:
173
AN XY:
727166
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000581
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00801
Gnomad4 SAS exome
AF:
0.000197
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000108
Gnomad4 OTH exome
AF:
0.000364
GnomAD4 genome
AF:
0.000289
AC:
44
AN:
152324
Hom.:
0
Cov.:
31
AF XY:
0.000309
AC XY:
23
AN XY:
74484
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000653
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00791
Gnomad4 SAS
AF:
0.000207
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000452
Hom.:
1
Bravo
AF:
0.000400
ExAC
AF:
0.000749
AC:
91
Asia WGS
AF:
0.00404
AC:
14
AN:
3478

ClinVar

Significance: Benign/Likely benign
Submissions summary: Uncertain:1Benign:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Neurodevelopmental disorder with progressive spasticity and brain white matter abnormalities Benign:2
Benign, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaApr 27, 2017This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to rule this variant out of causing disease. Therefore, this variant is classified as benign. -
Likely benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpFeb 03, 2023- -
Infantile spasms Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingClinical Molecular Genetics Laboratory, Johns Hopkins All Children's HospitalAug 03, 2017- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.30
BayesDel_addAF
Benign
0.00028
T
BayesDel_noAF
Pathogenic
0.23
CADD
Uncertain
25
DANN
Uncertain
0.98
DEOGEN2
Benign
0.24
.;.;.;T;.;.;.;.
Eigen
Uncertain
0.23
Eigen_PC
Uncertain
0.38
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.86
D;D;D;D;D;.;D;D
M_CAP
Benign
0.070
D
MetaRNN
Benign
0.010
T;T;T;T;T;T;T;T
MetaSVM
Uncertain
-0.24
T
MutationAssessor
Benign
0.41
.;.;N;N;N;N;.;.
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Pathogenic
0.80
T
PROVEAN
Uncertain
-2.8
D;D;.;N;N;N;N;N
REVEL
Uncertain
0.32
Sift
Uncertain
0.016
D;D;.;T;T;T;D;T
Sift4G
Benign
0.36
T;D;T;T;T;T;T;T
Polyphen
0.085, 0.73
.;.;.;B;P;P;.;.
Vest4
0.75, 0.69, 0.82, 0.82
MVP
0.93
MPC
0.81
ClinPred
0.088
T
GERP RS
5.7
Varity_R
0.26
gMVP
0.45

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
0.97
dbscSNV1_RF
Pathogenic
0.78
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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs77655188; hg19: chr2-171675181; API