2-170815865-C-G

Variant names:

• chr2-170815865-C-G
• rs6755102
• ENST00000663207.2:n.959G>C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The ENST00000663207.2(ERICH2-DT):​n.959G>C variant causes a non coding transcript exon change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000131 in 152,188 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 0.000013 (0 hom., cov: 33)
• Consequence: ERICH2-DT ENST00000663207.2 non_coding_transcript_exon
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.975
• Publications: 2 publications found

Genes affected

ERICH2-DT (HGNC:55686): (ERICH2 divergent transcript)

GAD1-AS1 (HGNC:40250):

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: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.77).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GAD1-AS1	NR_197761.1	n.1264G>C		non_coding_transcript_exon_variant	Exon 4 of 4
GAD1-AS1	NR_197762.1	n.1033G>C		non_coding_transcript_exon_variant	Exon 3 of 3
GAD1-AS1	NR_197763.1	n.1090G>C		non_coding_transcript_exon_variant	Exon 3 of 3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ERICH2-DT	ENST00000663207.2	n.959G>C		non_coding_transcript_exon_variant	Exon 2 of 2
GAD1	ENST00000454603.5	c.-64+2443C>G		intron_variant	Intron 1 of 3	4		ENSP00000402366.1
ERICH2-DT	ENST00000728834.1	n.358+989G>C		intron_variant	Intron 1 of 4

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152188 Hom.: 0 Cov.: 33

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: 0.000478

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

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152188 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74338

⚠️ 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: 41450

American (AMR) AF: 0.00 AC: 0 AN: 15288

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5166

South Asian (SAS) AF: 0.00 AC: 0 AN: 4836

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68042

Other (OTH) AF: 0.000478 AC: 1 AN: 2094

⚠️ 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.

Alfa AF: 0.00 Hom.: 4

Bravo AF: 0.0000113

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.77
CADD	Benign	2.6
DANN	Benign	0.51
PhyloP100		-0.97
PromoterAI		0.062	Neutral

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs6755102; hg19: chr2-171672375;