2-170832083-C-T

Variant names:

• chr2-170832083-C-T
• rs10191129
• NM_000817.3:c.547+891C>T

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_Strong BS1 BS2

The NM_000817.3(GAD1):​c.547+891C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00116 in 152,040 control chromosomes in the GnomAD database, including 4 homozygotes. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: 𝑓 0.0012 (4 hom., cov: 31)
• Consequence: GAD1 NM_000817.3 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.167
• Publications: 7 publications found

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)

ACMG classification

Our verdict: Benign. The variant received -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.84).
• BS1: Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.00116 (176/152040) while in subpopulation EAS AF = 0.0315 (163/5178). AF 95% confidence interval is 0.0275. There are 4 homozygotes in GnomAd4. There are 91 alleles in the male GnomAd4 subpopulation. Median coverage is 31. This position passed quality control check.
• BS2: High Homozygotes in GnomAd4 at 4 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GAD1	NM_000817.3	c.547+891C>T		intron_variant	Intron 5 of 16	ENST00000358196.8	NP_000808.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GAD1	ENST00000358196.8	c.547+891C>T		intron_variant	Intron 5 of 16	1	NM_000817.3	ENSP00000350928.3

Frequencies

GnomAD3 genomes AF: 0.00116 AC: 176 AN: 151924 Hom.: 4 Cov.: 31

Gnomad AFR AF: 0.0000726

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000656

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.0314

Gnomad SAS AF: 0.00104

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000441

Gnomad OTH AF: 0.000478

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.00116 AC: 176 AN: 152040 Hom.: 4 Cov.: 31 AF XY: 0.00122 AC XY: 91 AN XY: 74302

African (AFR) AF: 0.0000723 AC: 3 AN: 41466

American (AMR) AF: 0.0000655 AC: 1 AN: 15262

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.0315 AC: 163 AN: 5178

South Asian (SAS) AF: 0.00104 AC: 5 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10542

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000441 AC: 3 AN: 67978

Other (OTH) AF: 0.000473 AC: 1 AN: 2112

Alfa AF: 0.000226 Hom.: 189

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	6.4
DANN	Benign	0.67
PhyloP100		0.17
Mutation Taster		=100/0	polymorphism

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

Other links and lift over

dbSNP: rs10191129; hg19: chr2-171688593;