12-48131394-G-C

Variant names:

• chr12-48131394-G-C
• rs202143236
• NM_000289.6:c.237+1G>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_000289.6(PFKM):​c.237+1G>C variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: PFKM NM_000289.6 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 10.0
• Publications: 5 publications found

Genes affected

PFKM (HGNC:8877): (phosphofructokinase, muscle) Three phosphofructokinase isozymes exist in humans: muscle, liver and platelet. These isozymes function as subunits of the mammalian tetramer phosphofructokinase, which catalyzes the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate. Tetramer composition varies depending on tissue type. This gene encodes the muscle-type isozyme. Mutations in this gene have been associated with glycogen storage disease type VII, also known as Tarui disease. Alternatively spliced transcript variants have been described.[provided by RefSeq, Nov 2009]

PFKM Gene-Disease associations (from GenCC):

• glycogen storage disease VII

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

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.033290654 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-48131394-G-C is Pathogenic according to our data. Variant chr12-48131394-G-C is described in ClinVar as Pathogenic. ClinVar VariationId is 1453463.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PFKM	NM_000289.6	c.237+1G>C		splice_donor_variant, intron_variant	Intron 4 of 22	ENST00000359794.11	NP_000280.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PFKM	ENST00000359794.11	c.237+1G>C		splice_donor_variant, intron_variant	Intron 4 of 22	1	NM_000289.6	ENSP00000352842.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Glycogen storage disease, type VII Pathogenic:1

Apr 10, 2021

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. Studies have shown that disruption of this splice site is associated with skipping of exon 4 (also known as exon 5) but is expected to preserve the integrity of the reading frame (PMID:8444874). Disruption of this splice site has been observed in individual(s) with glycogen storage disease (PMID: 8444874, 8037209). This variant is not present in population databases (ExAC no frequency). This sequence change affects a donor splice site in intron 4 of the PFKM gene. RNA analysis indicates that this variant induces altered splicing and likely results in a shortened protein product.

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	33
DANN	Uncertain	0.99
DEOGEN2	Benign	0.0	.;.;.;.;.;.;.;.;.;.;.;.;.;.
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Benign	0.0	.;.;.;.;.;.;.;.;.;.;.;.;.;.
MetaRNN	Benign	0.0	.;.;.;.;.;.;.;.;.;.;.;.;.;.
MutationAssessor	Benign	0.0	.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100		10
PROVEAN	Benign	0.0	.;.;.;.;.;.;.;.;.;.;.;.;.;.
REVEL	Benign	0.0
Sift	Pathogenic	0.0	.;.;.;.;.;.;.;.;.;.;.;.;.;.
Sift4G	Pathogenic	0.0	.;.;.;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.0
GERP RS		3.9
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.97		Position offset: -1

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

Other links and lift over

dbSNP: rs202143236; hg19: chr12-48525177;