3-136001822-C-A

Position:

• chr3-136001822-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_002718.5(PPP2R3A):​c.324C>A​(p.Asn108Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,806 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 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. N108S) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: PPP2R3A NM_002718.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.293

Genes affected

PPP2R3A (HGNC:9307): (protein phosphatase 2 regulatory subunit B''alpha) This gene encodes one of the regulatory subunits of the protein phosphatase 2. Protein phosphatase 2 (formerly named type 2A) is one of the four major Ser/Thr phosphatases and is implicated in the negative control of cell growth and division. Protein phosphatase 2 holoenzymes are heterotrimeric proteins composed of a structural subunit A, a catalytic subunit C, and a regulatory subunit B. The regulatory subunit is encoded by a diverse set of genes that have been grouped into the B/PR55, B'/PR61, and B''/PR72 families. These different regulatory subunits confer distinct enzymatic specificities and intracellular localizations to the holozenzyme. The product of this gene belongs to the B'' family. The B'' family has been further divided into subfamilies. The product of this gene belongs to the alpha subfamily of regulatory subunit B''. Alternative splicing results in multiple transcript variants encoding different isoforms.[provided by RefSeq, Jun 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.37303662).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PPP2R3A	NM_002718.5	c.324C>A	p.Asn108Lys	missense_variant	2/14	ENST00000264977.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PPP2R3A	ENST00000264977.8	c.324C>A	p.Asn108Lys	missense_variant	2/14	1	NM_002718.5	P3
PPP2R3A	ENST00000490467.5	c.-213-25010C>A		intron_variant		2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461806 Hom.: 0 Cov.: 47 AF XY: 0.00000275 AC XY: 2 AN XY: 727202

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000371 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 29, 2022

The c.324C>A (p.N108K) alteration is located in exon 2 (coding exon 1) of the PPP2R3A gene. This alteration results from a C to A substitution at nucleotide position 324, causing the asparagine (N) at amino acid position 108 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.48
BayesDel_addAF	Benign	-0.18	T
BayesDel_noAF	Benign	-0.50
CADD	Benign	13
DANN	Uncertain	0.99
DEOGEN2	Benign	0.031	T
Eigen	Benign	-0.14
Eigen_PC	Benign	-0.19
FATHMM_MKL	Benign	0.47	N
LIST_S2	Benign	0.77	T
M_CAP	Benign	0.019	T
MetaRNN	Benign	0.37	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.7	L
MutationTaster	Benign	1.0	D;N
PrimateAI	Uncertain	0.64	T
PROVEAN	Benign	-1.3	N
REVEL	Benign	0.14
Sift	Uncertain	0.0030	D
Sift4G	Uncertain	0.059	T
Polyphen		0.92	P
Vest4		0.69
MutPred		0.25		Gain of helix (P = 0.0225);
MVP		0.043
MPC		0.40
ClinPred		0.96	D
GERP RS		-0.79
Varity_R		0.34
gMVP		0.27

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

LitVar

Other links and lift over

dbSNP: rs748461075; hg19: chr3-135720664;