chr4-105369746-CACTT-C

Variant names:

• chr4-105369746-CACTT-C
• rs755508592
• NM_176869.3:c.980_983delAAGT

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_176869.3(PPA2):​c.980_983delAAGT​(p.Gln327ArgfsTer9) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000044 in 1,590,728 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000042 (0 hom.)
• Consequence: PPA2 NM_176869.3 frameshift
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.55
• Publications: 1 publications found

Genes affected

PPA2 (HGNC:28883): (inorganic pyrophosphatase 2) The protein encoded by this gene is localized to the mitochondrion, is highly similar to members of the inorganic pyrophosphatase (PPase) family, and contains the signature sequence essential for the catalytic activity of PPase. PPases catalyze the hydrolysis of pyrophosphate to inorganic phosphate, which is important for the phosphate metabolism of cells. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. [provided by RefSeq, Jul 2008]

PPA2 Gene-Disease associations (from GenCC):

• sudden cardiac failure, infantile

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy

  Inheritance: AR Classification: STRONG Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0249 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_176869.3. 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
	PPA2	NM_176869.3	MANE Select	c.980_983delAAGT	p.Gln327ArgfsTer9	frameshift	Exon 12 of 12	NP_789845.1	Q9H2U2-1
	PPA2	NM_006903.4		c.893_896delAAGT	p.Gln298ArgfsTer9	frameshift	Exon 11 of 11	NP_008834.3	Q9H2U2-3
	PPA2	NM_176866.2		c.674_677delAAGT	p.Gln225ArgfsTer9	frameshift	Exon 8 of 8	NP_789842.2	Q9H2U2-6

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PPA2	ENST00000341695.10	TSL:1 MANE Select	c.980_983delAAGT	p.Gln327ArgfsTer9	frameshift	Exon 12 of 12	ENSP00000343885.5	Q9H2U2-1
	PPA2	ENST00000348706.9	TSL:1	c.893_896delAAGT	p.Gln298ArgfsTer9	frameshift	Exon 11 of 11	ENSP00000313061.8	Q9H2U2-3
	PPA2	ENST00000432483.6	TSL:1	c.674_677delAAGT	p.Gln225ArgfsTer9	frameshift	Exon 8 of 8	ENSP00000389957.2	Q9H2U2-6

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152040 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000279 AC: 7 AN: 251110 AF XY: 0.0000147

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000203

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: 0.00000417 AC: 6 AN: 1438688 Hom.: 0 AF XY: 0.00000279 AC XY: 2 AN XY: 716942

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 32876

American (AMR) AF: 0.000134 AC: 6 AN: 44694

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26012

East Asian (EAS) AF: 0.00 AC: 0 AN: 39568

South Asian (SAS) AF: 0.00 AC: 0 AN: 85764

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53370

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5726

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1090978

Other (OTH) AF: 0.00 AC: 0 AN: 59700

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000583533), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152040 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74250

African (AFR) AF: 0.00 AC: 0 AN: 41400

American (AMR) AF: 0.0000655 AC: 1 AN: 15268

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4808

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10572

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68024

Other (OTH) AF: 0.00 AC: 0 AN: 2088

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	3	-	not provided (3)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		3.6
Mutation Taster		=99/101	disease causing

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: rs755508592; hg19: chr4-106290903;