chr5-146600431-T-C

Position:

• chr5-146600431-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_181675.4(PPP2R2B):​c.820A>G​(p.Arg274Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: PPP2R2B NM_181675.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.61

Genes affected

PPP2R2B (HGNC:9305): (protein phosphatase 2 regulatory subunit Bbeta) The product of this gene belongs to the phosphatase 2 regulatory subunit B family. Protein phosphatase 2 is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The B regulatory subunit might modulate substrate selectivity and catalytic activity. This gene encodes a beta isoform of the regulatory subunit B55 subfamily. Defects in this gene cause autosomal dominant spinocerebellar ataxia 12 (SCA12), a disease caused by degeneration of the cerebellum, sometimes involving the brainstem and spinal cord, and in resulting in poor coordination of speech and body movements. Multiple alternatively spliced variants, which encode different isoforms, have been identified for this gene. The 5' UTR of some of these variants includes a CAG trinucleotide repeat sequence (7-28 copies) that can be expanded to 55-78 copies in cases of SCA12. [provided by RefSeq, Jul 2016]

(HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), PPP2R2B. . Gene score misZ 2.2458 (greater than the threshold 3.09). Trascript score misZ 3.5161 (greater than threshold 3.09). GenCC has associacion of gene with spinocerebellar ataxia type 12.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PPP2R2B	NM_181675.4	c.820A>G	p.Arg274Gly	missense_variant	8/10	ENST00000394411.9
CTB-99A3.1	XR_007058986.1	n.229-6538T>C		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PPP2R2B	ENST00000394411.9	c.820A>G	p.Arg274Gly	missense_variant	8/10	2	NM_181675.4	P3
	ENST00000512730.1	n.247-6538T>C		intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Apr 25, 2023

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Uncertain	0.16	D
BayesDel_noAF	Uncertain	-0.010
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.55	D;.;.;D;.;.;.;.
Eigen	Benign	-0.035
Eigen_PC	Benign	-0.049
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Pathogenic	0.98	.;.;D;D;D;D;D;D
M_CAP	Uncertain	0.16	D
MetaRNN	Uncertain	0.56	D;D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.28	T
MutationAssessor	Pathogenic	3.5	H;.;.;H;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.83	D
PROVEAN	Pathogenic	-6.1	.;D;D;D;.;D;D;.
REVEL	Uncertain	0.46
Sift	Pathogenic	0.0	.;D;D;D;.;D;D;.
Sift4G	Uncertain	0.0030	D;D;D;D;D;D;D;D
Polyphen		0.28	B;.;B;B;.;P;B;B
Vest4		0.69
MutPred		0.36		Gain of loop (P = 0.0051);.;.;Gain of loop (P = 0.0051);.;.;.;.;
MVP		0.81
MPC		1.2
ClinPred		0.99	D
GERP RS		-1.7
Varity_R		0.88
gMVP		0.57

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr5-145979994;