2-170831044-T-C

Variant names:

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 0P and 10B. BP4_StrongBP6BP7BS1

The NM_000817.3(GAD1):c.399T>C(p.Asp133Asp) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000777 in 1,614,080 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00055 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00080 ( 1 hom. )

Consequence

GAD1
NM_000817.3 synonymous

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:3

Conservation

PhyloP100: 0.117

Publications

0 publications found

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]

GAD1 Gene-Disease associations (from GenCC):

early infantile epileptic encephalopathy
Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
developmental and epileptic encephalopathy 89
Inheritance: AR Classification: STRONG, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae)
spastic quadriplegic cerebral palsy
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
cerebral palsy, spastic quadriplegic, 1
Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics
neurodevelopmental disorder with progressive spasticity and brain white matter abnormalities
Inheritance: AR Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

GAD1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -10 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.54).

BP6

Variant 2-170831044-T-C is Benign according to our data. Variant chr2-170831044-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 332230.

BP7

Synonymous conserved (PhyloP=0.117 with no splicing effect.

BS1

Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000545 (83/152186) while in subpopulation NFE AF = 0.000926 (63/68040). AF 95% confidence interval is 0.000742. There are 0 homozygotes in GnomAd4. There are 38 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GAD1	NM_000817.3 link	c.399T>C	p.Asp133Asp	synonymous_variant	Exon 5 of 17	ENST00000358196.8	NP_000808.2	Q99259-1A0A0S2Z3V5Q8IVA8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GAD1	ENST00000358196.8 link	c.399T>C	p.Asp133Asp	synonymous_variant	Exon 5 of 17	1	NM_000817.3	ENSP00000350928.3		Q99259-1

Frequencies

GnomAD3 genomes

AF:

0.000545

AC:

AN:

152186

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000654

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:

0.000926

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.000569

AC:

143

AN:

251474

AF XY:

0.000618

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000318

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00112

Gnomad OTH exome

AF:

0.000489

GnomAD4 exome

AF:

0.000801

AC:

1171

AN:

1461894

Hom.:

Cov.:

AF XY:

0.000807

AC XY:

587

AN XY:

727248

show subpopulations

African (AFR)

AF:

0.000149

AC:

AN:

33480

American (AMR)

AF:

0.000268

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.0000383

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.0000348

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.0000562

AC:

AN:

53420

Middle Eastern (MID)

AF:

0.000693

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.000996

AC:

1108

AN:

1112012

Other (OTH)

AF:

0.000580

AC:

AN:

60396

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.472

Heterozygous variant carriers

145

217

290

362

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

126

168

210

<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:

0.000545

AC:

AN:

152186

Hom.:

Cov.:

AF XY:

0.000511

AC XY:

AN XY:

74344

show subpopulations

African (AFR)

AF:

0.000241

AC:

AN:

41436

American (AMR)

AF:

0.000654

AC:

AN:

15286

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5188

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10620

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.000926

AC:

AN:

68040

Other (OTH)

AF:

0.00

AC:

AN:

2088

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.505

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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:

0.000834

Hom.:

Bravo

AF:

0.000608

EpiCase

AF:

0.000818

EpiControl

AF:

0.00166

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Neurodevelopmental disorder with progressive spasticity and brain white matter abnormalities

Uncertain:1Benign:1

Jan 27, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

GAD1-related disorder

Benign:1

Feb 28, 2024

PreventionGenetics, part of Exact Sciences

Significance:Likely benign

Review Status:no assertion criteria provided

Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

not provided

Benign:1

May 01, 2024

CeGaT Center for Human Genetics Tuebingen

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

GAD1: BP4, BP7 -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.54

CADD

Benign

5.6

(source)

DANN

Benign

0.50

PhyloP100

0.12

Mutation Taster

=100/0

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over