rs200038732

Variant names:

• chr11-64758293-G-A
• rs200038732
• NM_005609.4:c.481C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PP2 PP3_Strong PP5

The NM_005609.4(PYGM):​c.481C>T​(p.Arg161Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000242 in 1,614,050 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000024 (0 hom.)
• Consequence: PYGM NM_005609.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:3
• Conservation: PhyloP100: 10.0
• Publications: 4 publications found

Genes affected

PYGM (HGNC:9726): (glycogen phosphorylase, muscle associated) This gene encodes a muscle enzyme involved in glycogenolysis. Highly similar enzymes encoded by different genes are found in liver and brain. Mutations in this gene are associated with McArdle disease (myophosphorylase deficiency), a glycogen storage disease of muscle. Alternative splicing results in multiple transcript variants.[provided by RefSeq, Sep 2009]

PYGM Gene-Disease associations (from GenCC):

• glycogen storage disease V

  Inheritance: AR, AD Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics, Genomics England PanelApp

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_005609.4
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 37 curated pathogenic missense variants (we use a threshold of 10). The gene has 5 curated benign missense variants. Gene score misZ: 0.046884 (below the threshold of 3.09). Trascript score misZ: 1.6804 (below the threshold of 3.09). GenCC associations: The gene is linked to glycogen storage disease V.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.948
• PP5: Variant 11-64758293-G-A is Pathogenic according to our data. Variant chr11-64758293-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 551832.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PYGM	NM_005609.4	c.481C>T	p.Arg161Cys	missense_variant	Exon 4 of 20	ENST00000164139.4	NP_005600.1
PYGM	NM_001164716.1	c.244-27C>T		intron_variant	Intron 1 of 17		NP_001158188.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PYGM	ENST00000164139.4	c.481C>T	p.Arg161Cys	missense_variant	Exon 4 of 20	1	NM_005609.4	ENSP00000164139.3
PYGM	ENST00000377432.7	c.244-27C>T		intron_variant	Intron 1 of 17	2		ENSP00000366650.3

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152106 Hom.: 0 Cov.: 32

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: 0.0000944

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000441

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000795 AC: 2 AN: 251436 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000239 AC: 35 AN: 1461826 Hom.: 0 Cov.: 34 AF XY: 0.0000220 AC XY: 16 AN XY: 727210

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000696 AC: 6 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53390

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000252 AC: 28 AN: 1111984

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152224 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74432

African (AFR) AF: 0.00 AC: 0 AN: 41534

American (AMR) AF: 0.00 AC: 0 AN: 15294

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5178

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.0000944 AC: 1 AN: 10598

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

European-Non Finnish (NFE) AF: 0.0000441 AC: 3 AN: 68012

Other (OTH) AF: 0.00 AC: 0 AN: 2106

Alfa AF: 0.00000465 Hom.: 0

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Glycogen storage disease, type V Pathogenic:2 Uncertain:3

Dec 27, 2023

Revvity Omics, Revvity

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Aug 02, 2023

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

May 09, 2017

Counsyl

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Mar 06, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 03, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 161 of the PYGM protein (p.Arg161Cys). This variant is present in population databases (rs200038732, gnomAD 0.002%). This missense change has been observed in individual(s) with glycogen storage disease type V (PMID: 17404776). ClinVar contains an entry for this variant (Variation ID: 551832). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Not Available"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Not Available"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.80
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.56
CADD	Pathogenic	34
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.76	D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Uncertain	0.26	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.8	H
PhyloP100		10
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-7.1	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MVP		0.96
MPC		0.98
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.89
gMVP		0.92
Mutation Taster		=17/83	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs200038732; hg19: chr11-64525765; COSMIC: COSV51215131; COSMIC: COSV51215131;