rs377311394

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_001044305.3(SMAP1):c.826A>G(p.Thr276Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,700 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

SMAP1
NM_001044305.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.637

Publications

1 publications found

Variant links:

Genes affected

SMAP1 (HGNC:19651): (small ArfGAP 1) The protein encoded by this gene is similar to the mouse stromal membrane-associated protein-1. This similarity suggests that this human gene product is also a type II membrane glycoprotein involved in the erythropoietic stimulatory activity of stromal cells. Alternate splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008]

SMAP1 links:

B3GAT2 (HGNC:922): (beta-1,3-glucuronyltransferase 2) The product of this gene is a transmembrane protein belonging to the glucuronyltransferase family, and catalyzes the transfer of a beta-1,3 linked glucuronic acid to a terminal galactose in different glycoproteins or glycolipids containing a Gal-beta-1-4GlcNAc or Gal-beta-1-3GlcNAc residue. The encoded protein is involved in the synthesis of the human natural killer-1 (HNK-1) carbohydrate epitope, a sulfated trisaccharide implicated in cellular migration and adhesion in the nervous system. [provided by RefSeq, Jul 2008]

B3GAT2 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.05657789).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMAP1	NM_001044305.3 link	c.826A>G	p.Thr276Ala	missense_variant	Exon 9 of 11	ENST00000370455.8	NP_001037770.1	Q8IYB5-1
B3GAT2	NM_080742.3 link	c.*4768T>C		3_prime_UTR_variant	Exon 4 of 4	ENST00000230053.11	NP_542780.1	Q9NPZ5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMAP1	ENST00000370455.8 link	c.826A>G	p.Thr276Ala	missense_variant	Exon 9 of 11	1	NM_001044305.3	ENSP00000359484.3		Q8IYB5-1
B3GAT2	ENST00000230053.11 link	c.*4768T>C		3_prime_UTR_variant	Exon 4 of 4	1	NM_080742.3	ENSP00000230053.6		Q9NPZ5

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152240

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.00000797

AC:

AN:

250800

AF XY:

0.00000738

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000545

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461460

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727010

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33466

American (AMR)

AF:

0.00

AC:

AN:

44688

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26124

East Asian (EAS)

AF:

0.0000252

AC:

AN:

39672

South Asian (SAS)

AF:

0.00

AC:

AN:

86194

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53398

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5766

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1111772

Other (OTH)

AF:

0.00

AC:

AN:

60380

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.525

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152240

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74388

show subpopulations

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

African (AFR)

AF:

0.0000241

AC:

AN:

41468

American (AMR)

AF:

0.00

AC:

AN:

15292

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3468

East Asian (EAS)

AF:

0.00

AC:

AN:

5200

South Asian (SAS)

AF:

0.00

AC:

AN:

4836

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10624

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68034

Other (OTH)

AF:

0.00

AC:

AN:

2090

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.375

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.0000113

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Mar 27, 2025

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The c.826A>G (p.T276A) alteration is located in exon 9 (coding exon 9) of the SMAP1 gene. This alteration results from a A to G substitution at nucleotide position 826, causing the threonine (T) at amino acid position 276 to be replaced by an alanine (A). 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

0.053

BayesDel_addAF

Benign

-0.49

BayesDel_noAF

Benign

-0.76

CADD

Benign

(source)

DANN

Benign

0.73

DEOGEN2

Benign

0.014

.;.;T;.

Eigen

Benign

-0.52

Eigen_PC

Benign

-0.39

FATHMM_MKL

Benign

0.50

LIST_S2

Benign

0.65

T;T;T;T

M_CAP

Benign

0.0048

MetaRNN

Benign

0.057

T;T;T;T

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.41

.;.;N;.

PhyloP100

0.64

PrimateAI

Benign

0.28

PROVEAN

Benign

0.0

N;N;N;.

REVEL

Benign

0.050

Sift

Benign

0.24

T;T;T;.

Sift4G

Benign

0.80

T;T;T;T

Polyphen

0.0010

B;B;B;.

Vest4

0.059

MVP

0.47

MPC

0.12

ClinPred

0.027

GERP RS

1.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.032

gMVP

0.14

Mutation Taster

=86/14

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

rs377311394

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over