14-50915373-C-T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM2PP3_ModeratePP5_Very_Strong

The NM_002863.5(PYGL):​c.1366G>A​(p.Val456Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000242 in 1,614,130 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000023 ( 1 hom. )

Consequence

PYGL
NM_002863.5 missense

Scores

16
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2O:1

Conservation

PhyloP100: 7.91

Publications

7 publications found
Variant links:
Genes affected
PYGL (HGNC:9725): (glycogen phosphorylase L) This gene encodes a homodimeric protein that catalyses the cleavage of alpha-1,4-glucosidic bonds to release glucose-1-phosphate from liver glycogen stores. This protein switches from inactive phosphorylase B to active phosphorylase A by phosphorylation of serine residue 15. Activity of this enzyme is further regulated by multiple allosteric effectors and hormonal controls. Humans have three glycogen phosphorylase genes that encode distinct isozymes that are primarily expressed in liver, brain and muscle, respectively. The liver isozyme serves the glycemic demands of the body in general while the brain and muscle isozymes supply just those tissues. In glycogen storage disease type VI, also known as Hers disease, mutations in liver glycogen phosphorylase inhibit the conversion of glycogen to glucose and results in moderate hypoglycemia, mild ketosis, growth retardation and hepatomegaly. Alternative splicing results in multiple transcript variants encoding different isoforms.[provided by RefSeq, Feb 2011]
PYGL Gene-Disease associations (from GenCC):
  • glycogen storage disease VI
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, PanelApp Australia, Genomics England PanelApp, Orphanet, Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.915
PP5
Variant 14-50915373-C-T is Pathogenic according to our data. Variant chr14-50915373-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 21328.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PYGLNM_002863.5 linkc.1366G>A p.Val456Met missense_variant Exon 11 of 20 ENST00000216392.8 NP_002854.3 P06737-1
PYGLNM_001163940.2 linkc.1264G>A p.Val422Met missense_variant Exon 10 of 19 NP_001157412.1 P06737-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PYGLENST00000216392.8 linkc.1366G>A p.Val456Met missense_variant Exon 11 of 20 1 NM_002863.5 ENSP00000216392.7 P06737-1
PYGLENST00000532462.5 linkc.1366G>A p.Val456Met missense_variant Exon 11 of 20 1 ENSP00000431657.1 E9PK47
PYGLENST00000544180.6 linkc.1264G>A p.Val422Met missense_variant Exon 10 of 19 2 ENSP00000443787.1 P06737-2
PYGLENST00000528757.2 linkn.243G>A non_coding_transcript_exon_variant Exon 2 of 2 3

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152118
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000358
AC:
9
AN:
251482
AF XY:
0.0000515
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000233
AC:
34
AN:
1461894
Hom.:
1
Cov.:
32
AF XY:
0.0000316
AC XY:
23
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
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:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000927
AC:
8
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000207
AC:
23
AN:
1112012
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.473
Heterozygous variant carriers
0
2
4
7
9
11
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
2
4
6
8
10
<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:
0.0000328
AC:
5
AN:
152236
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74426
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41538
American (AMR)
AF:
0.000131
AC:
2
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5182
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10590
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2106
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.435
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000420
Hom.:
0
Bravo
AF:
0.0000264
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000330
AC:
4
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:2Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Glycogen storage disease, type VI Pathogenic:2Other:1
May 22, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt PYGL protein function. ClinVar contains an entry for this variant (Variation ID: 21328). This missense change has been observed in individual(s) with glycogen storage disease type VI (PMID: 17705025, 21646031, 32892177). It has also been observed to segregate with disease in related individuals. This variant is present in population databases (rs113993979, gnomAD 0.01%). This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 456 of the PYGL protein (p.Val456Met). -

Nov 26, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: PYGL c.1366G>A (p.Val456Met) results in a conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 3.6e-05 in 251482 control chromosomes in the gnomAD database, including 1 homozygote. c.1366G>A has been reported in the literature in the compound heterozygous state in multiple individuals affected with clinical features of Glycogen storage disease, type VI (example, Beauchamp_2007, Davit-Spraul_2011, Hoogeveen_2016, Lu_2020), and was found to segregate with disease in 2 siblings. These data indicate that the variant is likely to be associated with disease. At least one publication reports a significant deficiency of PYGL function in compound heterozygous patient cells, however the impact of the p.Val456Met variant alone could not be determined (example, Beauchamp_2007). The following publications have been ascertained in the context of this evaluation (PMID: 17705025, 21646031, 26526422, 32892177). ClinVar contains an entry for this variant (Variation ID: 21328). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

-
GeneReviews
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.96
BayesDel_addAF
Pathogenic
0.41
D
BayesDel_noAF
Pathogenic
0.59
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.86
.;.;D
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
1.0
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D;D;D
M_CAP
Pathogenic
0.41
D
MetaRNN
Pathogenic
0.91
D;D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
4.4
.;.;H
PhyloP100
7.9
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-2.5
D;D;D
REVEL
Pathogenic
0.94
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0
D;D;D
Polyphen
1.0
.;.;D
Vest4
0.96
MVP
0.98
MPC
0.53
ClinPred
0.98
D
GERP RS
5.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.92
gMVP
0.93
Mutation Taster
=11/89
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs113993979; hg19: chr14-51382091; API