rs1347832021

Variant names:

• chr17-80117008-C-T
• rs1347832021
• NM_000152.5:c.2230C>T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 5P and 2B. PM1 PM2 PP2 BP4_Moderate

The NM_000152.5(GAA):​c.2230C>T​(p.Leu744Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,422 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L744P) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GAA NM_000152.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.29
• Publications: 0 publications found

Genes affected

GAA (HGNC:4065): (alpha glucosidase) This gene encodes lysosomal alpha-glucosidase, which is essential for the degradation of glycogen to glucose in lysosomes. The encoded preproprotein is proteolytically processed to generate multiple intermediate forms and the mature form of the enzyme. Defects in this gene are the cause of glycogen storage disease II, also known as Pompe's disease, which is an autosomal recessive disorder with a broad clinical spectrum. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2016]

GAA Gene-Disease associations (from GenCC):

• glycogen storage disease II

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Laboratory for Molecular Medicine, ClinGen, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp
• glycogen storage disease due to acid maltase deficiency, infantile onset

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• glycogen storage disease due to acid maltase deficiency, late-onset

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 12 uncertain in NM_000152.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 201 curated pathogenic missense variants (we use a threshold of 10). The gene has 50 curated benign missense variants. Gene score misZ: -0.63308 (below the threshold of 3.09). Trascript score misZ: -0.32889 (below the threshold of 3.09). GenCC associations: The gene is linked to glycogen storage disease due to acid maltase deficiency, infantile onset, glycogen storage disease II, glycogen storage disease due to acid maltase deficiency, late-onset.
• BP4: Computational evidence support a benign effect (MetaRNN=0.24060181).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000152.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GAA	NM_000152.5	MANE Select	c.2230C>T	p.Leu744Phe	missense	Exon 16 of 20	NP_000143.2	P10253
	GAA	NM_001079803.3		c.2230C>T	p.Leu744Phe	missense	Exon 17 of 21	NP_001073271.1	P10253
	GAA	NM_001079804.3		c.2230C>T	p.Leu744Phe	missense	Exon 16 of 20	NP_001073272.1	P10253

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GAA	ENST00000302262.8	TSL:1 MANE Select	c.2230C>T	p.Leu744Phe	missense	Exon 16 of 20	ENSP00000305692.3	P10253
	GAA	ENST00000390015.7	TSL:1	c.2230C>T	p.Leu744Phe	missense	Exon 17 of 21	ENSP00000374665.3	P10253
	GAA	ENST00000933406.1		c.2245C>T	p.Leu749Phe	missense	Exon 16 of 20	ENSP00000603465.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000399 AC: 1 AN: 250916 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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461422 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727032

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

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

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

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52970

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111998

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Glycogen storage disease, type II (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.083
BayesDel_addAF	Benign	-0.084	T
BayesDel_noAF	Benign	-0.26
CADD	Benign	18
DANN	Benign	0.32
DEOGEN2	Uncertain	0.48	T
Eigen	Benign	-0.61
Eigen_PC	Benign	-0.29
FATHMM_MKL	Benign	0.67	D
LIST_S2	Benign	0.79	T
M_CAP	Benign	0.054	D
MetaRNN	Benign	0.24	T
MetaSVM	Benign	-0.68	T
MutationAssessor	Benign	-2.0	N
PhyloP100		2.3
PrimateAI	Benign	0.43	T
PROVEAN	Benign	4.4	N
REVEL	Benign	0.22
Sift	Benign	1.0	T
Sift4G	Benign	1.0	T
Polyphen		0.0010	B
Vest4		0.32
MutPred		0.64		Gain of phosphorylation at T739 (P = 0.2816)
MVP		0.69
MPC		0.12
ClinPred		0.23	T
GERP RS		4.0
Varity_R		0.16
gMVP		0.65
Mutation Taster		=52/48	polymorphism

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

Other links and lift over

dbSNP: rs1347832021; hg19: chr17-78090807;