VCV002637494.2 - ClinVar

NM_004130.4(GYG1):c.7+2T>C

Germline

Classification

The aggregate germline classification for this variant, typically for a monogenic or Mendelian disorder as in the ACMG/AMP guidelines, or for response to a drug. This value is calculated by NCBI based on data from submitters. Read our rules for calculating the aggregate classification.

(2)

Stars represent the aggregate review status, or the level of review supporting the aggregate germline classification for this VCV record. This value is calculated by NCBI based on data from submitters. Read our rules for calculating the review status. The number of submissions which contribute to this review status is shown in parentheses.

Likely pathogenic

criteria provided, multiple submitters, no conflicts

Somatic

No data submitted for somatic clinical impact

Somatic

No data submitted for oncogenicity

Variant Details

Identifiers

NM_004130.4(GYG1):c.7+2T>C

Variation ID: 2637494 Accession: VCV002637494.2

Type and length

single nucleotide variant, 1 bp

Location

Cytogenetic: 3q24 3: 148991649 (GRCh38) [ NCBI UCSC ] 3: 148709436 (GRCh37) [ NCBI UCSC ]

Timeline in ClinVar

	First in ClinVar Help The date this variant first appeared in ClinVar with each type of classification.	Last submission Help The date of the most recent submission for each type of classification for this variant.	Last evaluated Help The most recent date that a submitter evaluated this variant for each type of classification.
Germline	Nov 20, 2023	Feb 28, 2024	Oct 26, 2023

HGVS

Nucleotide	Protein	Molecular consequence
NM_004130.4:c.7+2T>C MANE Select Help Transcripts from the Matched Annotation from the NCBI and EMBL-EBI (MANE) collaboration.		splice donor
NM_001184720.2:c.7+2T>C		splice donor
NM_001184721.2:c.7+2T>C		splice donor
NC_000003.12:g.148991649T>C
NC_000003.11:g.148709436T>C
NG_027677.1:g.5242T>C
NG_027677.2:g.5111T>C
NG_170747.1:g.571T>C

... more HGVS ... less HGVS

Protein change

Other names

Canonical SPDI

NC_000003.12:148991648:T:C

Functional consequence Help The effect of the variant on RNA or protein function, based on experimental evidence from submitters.

Global minor allele frequency (GMAF) Help The global minor allele frequency calculated by the 1000 Genomes Project. The minor allele at this location is indicated in parentheses and may be different from the allele represented by this VCV record.

Allele frequency Help The frequency of the allele represented by this VCV record.

Links

VarSome

Genes

Gene	OMIM	ClinGen Gene Dosage Sensitivity Curation		Variation Viewer Help Links to Variation Viewer, a genome browser to view variation data from NCBI databases.	Related variants
Gene	OMIM	HI score Help The haploinsufficiency score for the gene, curated by ClinGen’s Dosage Sensitivity Curation task team.	TS score Help The triplosensitivity score for the gene, curated by ClinGen’s Dosage Sensitivity Curation task team.		Within gene Help The number of variants in ClinVar that are contained within this gene, with a link to view the list of variants.	All Help The number of variants in ClinVar for this gene, including smaller variants within the gene and larger CNVs that overlap or fully contain the gene.
GYG1		-	-	GRCh38 GRCh37	272	309
LOC129937737	-	-	-	GRCh38	-	21

Conditions - Germline

Condition Help The condition for this variant-condition (RCV) record in ClinVar.	Classification Help The aggregate germline classification for this variant-condition (RCV) record in ClinVar. The number of submissions that contribute to this aggregate classification is shown in parentheses. (# of submissions)	Review status Help The aggregate review status for this variant-condition (RCV) record in ClinVar. This value is calculated by NCBI based on data from submitters. Read our rules for calculating the review status.	Last evaluated Help The most recent date that a submitter evaluated this variant for the condition.	Variation/condition record Help The RCV accession number, with most recent version number, for the variant-condition record, with a link to the RCV web page.
Polyglucosan body myopathy type 2	Likely pathogenic (1)	criteria provided, single submitter	Oct 26, 2023	RCV003404792.1
Glycogen storage disease XV Polyglucosan body myopathy type 2	Likely pathogenic (1)	criteria provided, single submitter	Jun 20, 2023	RCV003778344.2

Submissions - Germline

Classification Help The submitted germline classification for each SCV record. (Last evaluated)	Review status Help Stars represent the review status, or the level of review supporting the submitted (SCV) record. This value is calculated by NCBI based on data from the submitter. Read our rules for calculating the review status. This column also includes a link to the submitter’s assertion criteria if provided, and the collection method. (Assertion criteria)	Condition Help The condition for the classification, provided by the submitter for this submitted (SCV) record. This column also includes the affected status and allele origin of individuals observed with this variant.	Submitter Help The submitting organization for this submitted (SCV) record. This column also includes the SCV accession and version number, the date this SCV first appeared in ClinVar, and the date that this SCV was last updated in ClinVar.	More information Help This column includes more information supporting the classification, including citations, the comment on classification, and detailed evidence provided as observations of the variant by the submitter.
Likely pathogenic (Oct 26, 2023)	criteria provided, single submitter (LabCorp Variant Classification Summary - May 2015) Method: clinical testing	Polyglucosan body myopathy type 2 Affected status: unknown Allele origin: germline	Women's Health and Genetics/Laboratory Corporation of America, LabCorp Accession: SCV004122202.1 First in ClinVar: Nov 20, 2023 Last updated: Nov 20, 2023	Comment: Variant summary: GYG1 c.7+2T>C is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to … (more) Variant summary: GYG1 c.7+2T>C is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Four predict the variant abolishes a 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 135342 control chromosomes. To our knowledge, no occurrence of c.7+2T>C in individuals affected with Polyglucosan Body Myopathy Type 2 and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as likely pathogenic. (less)
Likely pathogenic (Jun 20, 2023)	criteria provided, single submitter (Invitae Variant Classification Sherloc (09022015)) Method: clinical testing	Polyglucosan body myopathy type 2 Glycogen storage disease XV Explanation for multiple conditions: Uncertain. The variant was classified for several related diseases, possibly a spectrum of disease; the variant may be associated with one or more the diseases. Affected status: unknown Allele origin: germline	Labcorp Genetics (formerly Invitae), Labcorp Accession: SCV004597163.1 First in ClinVar: Feb 28, 2024 Last updated: Feb 28, 2024	Publications: PubMed (3) PubMed: 16199547‚ 20357282‚ 25272951 Comment: Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the … (more) Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This variant has not been reported in the literature in individuals affected with GYG1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 1 of the GYG1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in GYG1 are known to be pathogenic (PMID: 20357282, 25272951). (less)

Comment:

Variant summary: GYG1 c.7+2T>C is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Four predict the variant abolishes a 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 135342 control chromosomes. To our knowledge, no occurrence of c.7+2T>C in individuals affected with Polyglucosan Body Myopathy Type 2 and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as likely pathogenic.

Comment:

Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This variant has not been reported in the literature in individuals affected with GYG1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 1 of the GYG1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in GYG1 are known to be pathogenic (PMID: 20357282, 25272951).

Germline Functional Evidence

There is no functional evidence in ClinVar for this variation. If you have generated functional data for this variation, please consider submitting that data to ClinVar.

Comment:

Citations for germline classification of this variant

Title	Author	Journal	Year	Link
A new muscle glycogen storage disease associated with glycogenin-1 deficiency.	Malfatti E	Annals of neurology	2014	PMID: 25272951
Glycogenin-1 deficiency and inactivated priming of glycogen synthesis.	Moslemi AR	The New England journal of medicine	2010	PMID: 20357282
Splicing in action: assessing disease causing sequence changes.	Baralle D	Journal of medical genetics	2005	PMID: 16199547

Text-mined citations for this variant ...

Record last updated Sep 30, 2024

ClinVar Genomic variation as it relates to human health

NM_004130.4(GYG1):c.7+2T>C

Variant Details

Genes

Conditions - Germline

Submissions - Germline

Germline Functional Evidence

Citations for germline classification of this variant

Text-mined citations for this variant ...