12-111446775-C-G

Variant names:

• chr12-111446775-C-G
• rs753938825
• NM_005475.3:c.755C>G

Variant summary

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

The NM_005475.3(SH2B3):​c.755C>G​(p.Ala252Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000572 in 1,399,120 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000057 (0 hom.)
• Consequence: SH2B3 NM_005475.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.29

Genes affected

SH2B3 (HGNC:29605): (SH2B adaptor protein 3) This gene encodes a member of the SH2B adaptor family of proteins, which are involved in a range of signaling activities by growth factor and cytokine receptors. The encoded protein is a key negative regulator of cytokine signaling and plays a critical role in hematopoiesis. Mutations in this gene have been associated with susceptibility to celiac disease type 13 and susceptibility to insulin-dependent diabetes mellitus. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2014]

ATXN2 (HGNC:10555): (ataxin 2) This gene belongs to a group of genes that is associated with microsatellite-expansion diseases, a class of neurological and neuromuscular disorders caused by expansion of short stretches of repetitive DNA. The protein encoded by this gene has two globular domains near the N-terminus, one of which contains a clathrin-mediated trans-Golgi signal and an endoplasmic reticulum exit signal. The encoded cytoplasmic protein localizes to the endoplasmic reticulum and plasma membrane, is involved in endocytosis, and modulates mTOR signals, modifying ribosomal translation and mitochondrial function. The N-terminal region of the protein contains a polyglutamine tract of 14-31 residues that can be expanded in the pathogenic state to 32-200 residues. Intermediate length expansions of this tract increase susceptibility to amyotrophic lateral sclerosis, while long expansions of this tract result in spinocerebellar ataxia-2, an autosomal-dominantly inherited, neurodegenerative disorder. Genome-wide association studies indicate that loss-of-function mutations in this gene may be associated with susceptibility to type I diabetes, obesity and hypertension. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2016]

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=0.26639473).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SH2B3	NM_005475.3	c.755C>G	p.Ala252Gly	missense_variant	Exon 3 of 8	ENST00000341259.7	NP_005466.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SH2B3	ENST00000341259.7	c.755C>G	p.Ala252Gly	missense_variant	Exon 3 of 8	1	NM_005475.3	ENSP00000345492.2
SH2B3	ENST00000538307.1	c.149C>G	p.Ala50Gly	missense_variant	Exon 2 of 7	2		ENSP00000440597.1
ATXN2	ENST00000642389.2	n.*171-2588G>C		intron_variant	Intron 26 of 26			ENSP00000496055.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000244 AC: 5 AN: 204652 Hom.: 0 AF XY: 0.0000278 AC XY: 3 AN XY: 108004

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 SAS exome AF: 0.0000500

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000426

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000572 AC: 8 AN: 1399120 Hom.: 0 Cov.: 29 AF XY: 0.00000872 AC XY: 6 AN XY: 688248

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: 0.0000132

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000649

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.0000415 AC: 5

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Mar 14, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.755C>G (p.A252G) alteration is located in exon 3 (coding exon 2) of the SH2B3 gene. This alteration results from a C to G substitution at nucleotide position 755, causing the alanine (A) at amino acid position 252 to be replaced by a glycine (G). 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	Benign	0.19
BayesDel_addAF	Benign	-0.16	T
BayesDel_noAF	Benign	-0.33
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.79	D;.
Eigen	Benign	-0.25
Eigen_PC	Benign	-0.36
FATHMM_MKL	Benign	0.50	D
LIST_S2	Uncertain	0.87	D;D
M_CAP	Benign	0.075	D
MetaRNN	Benign	0.27	T;T
MetaSVM	Benign	-0.66	T
MutationAssessor	Benign	1.9	L;.
PrimateAI	Benign	0.40	T
PROVEAN	Uncertain	-2.6	D;D
REVEL	Benign	0.12
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.021	D;D
Polyphen		0.76	P;P
Vest4		0.33
MutPred		0.38		Gain of relative solvent accessibility (P = 0.0479);.;
MVP		0.87
MPC		0.28
ClinPred		0.58	D
GERP RS		4.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.23
gMVP		0.41

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: rs753938825; hg19: chr12-111884579;