rs1771451558

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_001044305.3(SMAP1):​c.901T>A​(p.Ser301Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,886 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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: 0.0000021 ( 0 hom. )

Consequence

SMAP1
NM_001044305.3 missense

Scores

1
6
12

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.28

Publications

0 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]
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]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.38800496).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMAP1NM_001044305.3 linkc.901T>A p.Ser301Thr missense_variant Exon 9 of 11 ENST00000370455.8 NP_001037770.1 Q8IYB5-1
B3GAT2NM_080742.3 linkc.*4693A>T 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
SMAP1ENST00000370455.8 linkc.901T>A p.Ser301Thr missense_variant Exon 9 of 11 1 NM_001044305.3 ENSP00000359484.3 Q8IYB5-1
B3GAT2ENST00000230053.11 linkc.*4693A>T 3_prime_UTR_variant Exon 4 of 4 1 NM_080742.3 ENSP00000230053.6 Q9NPZ5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152220
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461666
Hom.:
0
Cov.:
30
AF XY:
0.00000138
AC XY:
1
AN XY:
727106
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39672
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86238
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111862
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152220
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74370
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41454
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000312
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Mar 22, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.901T>A (p.S301T) alteration is located in exon 9 (coding exon 9) of the SMAP1 gene. This alteration results from a T to A substitution at nucleotide position 901, causing the serine (S) at amino acid position 301 to be replaced by a threonine (T). 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
0.17
BayesDel_addAF
Benign
-0.049
T
BayesDel_noAF
Benign
-0.31
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Benign
0.040
.;.;T;.
Eigen
Uncertain
0.59
Eigen_PC
Uncertain
0.60
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.91
D;D;D;D
M_CAP
Benign
0.047
D
MetaRNN
Benign
0.39
T;T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Uncertain
2.5
.;.;M;.
PhyloP100
7.3
PrimateAI
Uncertain
0.70
T
PROVEAN
Benign
-1.1
N;N;N;.
REVEL
Benign
0.18
Sift
Benign
0.21
T;T;T;.
Sift4G
Benign
0.29
T;T;T;T
Polyphen
1.0
D;D;P;.
Vest4
0.55
MVP
0.47
MPC
0.35
ClinPred
0.94
D
GERP RS
5.6
Varity_R
0.24
gMVP
0.77
Mutation Taster
=53/47
polymorphism

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

Other links and lift over

dbSNP: rs1771451558; hg19: chr6-71566673; API