5-146590061-G-C

Variant names:

• chr5-146590061-G-C
• rs141962233
• NM_181675.4:c.1218C>G

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_181675.4(PPP2R2B):​c.1218C>G​(p.Val406Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. V406V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PPP2R2B NM_181675.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.00200
• Publications: 0 publications found

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]

PPP2R2B Gene-Disease associations (from GenCC):

• spinocerebellar ataxia type 12

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet

ENSG00000304935 (HGNC:):

ENSG00000250407 (HGNC:58421):

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.49).
• BP7: Synonymous conserved (PhyloP=-0.002 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_181675.4. 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
	PPP2R2B	NM_181675.4	MANE Select	c.1218C>G	p.Val406Val	synonymous	Exon 10 of 10	NP_858061.3	Q00005-1
	PPP2R2B	NM_181674.3		c.1416C>G	p.Val472Val	synonymous	Exon 10 of 10	NP_858060.2	Q00005-5
	PPP2R2B	NM_001271900.2		c.1392C>G	p.Val464Val	synonymous	Exon 11 of 11	NP_001258829.1	Q00005-4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PPP2R2B	ENST00000394411.9	TSL:2 MANE Select	c.1218C>G	p.Val406Val	synonymous	Exon 10 of 10	ENSP00000377933.3	Q00005-1
	PPP2R2B	ENST00000394414.5	TSL:1	c.1416C>G	p.Val472Val	synonymous	Exon 10 of 10	ENSP00000377936.1	Q00005-5
	PPP2R2B	ENST00000394409.7	TSL:1	c.1218C>G	p.Val406Val	synonymous	Exon 9 of 9	ENSP00000377931.4	Q00005-1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461888 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

⚠️ 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: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.49
CADD	Benign	2.6
DANN	Benign	0.72
PhyloP100		-0.0020

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs141962233; hg19: chr5-145969624;