NM_018344.6:c.1346C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PM5PP3_Moderate

The NM_018344.6(SLC29A3):​c.1346C>T​(p.Thr449Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000105 in 1,614,028 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T449R) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000011 ( 0 hom. )

Consequence

SLC29A3
NM_018344.6 missense

Scores

5
10
3

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.91

Publications

17 publications found
Variant links:
Genes affected
SLC29A3 (HGNC:23096): (solute carrier family 29 member 3) This gene encodes a nucleoside transporter. The encoded protein plays a role in cellular uptake of nucleosides, nucleobases, and their related analogs. Mutations in this gene have been associated with H syndrome, which is characterized by cutaneous hyperpigmentation and hypertrichosis, hepatosplenomegaly, heart anomalies, and hypogonadism. A related disorder, PHID (pigmented hypertrichosis with insulin-dependent diabetes mellitus), has also been associated with mutations at this locus. Alternatively spliced transcript variants have been described.[provided by RefSeq, Mar 2010]
SLC29A3 Gene-Disease associations (from GenCC):
  • H syndrome
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet
  • dysosteosclerosis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr10-71362526-C-G is described in CliVar as Pathogenic. Clinvar id is 569.Status of the report is criteria_provided_single_submitter, 1 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.848

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SLC29A3NM_018344.6 linkc.1346C>T p.Thr449Met missense_variant Exon 6 of 6 ENST00000373189.6 NP_060814.4 Q9BZD2-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SLC29A3ENST00000373189.6 linkc.1346C>T p.Thr449Met missense_variant Exon 6 of 6 1 NM_018344.6 ENSP00000362285.5 Q9BZD2-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152166
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
GnomAD2 exomes
AF:
0.0000318
AC:
8
AN:
251296
AF XY:
0.0000368
show subpopulations
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000109
AC:
16
AN:
1461862
Hom.:
0
Cov.:
34
AF XY:
0.0000165
AC XY:
12
AN XY:
727232
show subpopulations
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:
39700
South Asian (SAS)
AF:
0.000151
AC:
13
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53390
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1112010
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.509
Heterozygous variant carriers
0
2
3
5
6
8
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:
152166
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74336
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
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
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

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

Submissions by phenotype

H syndrome Uncertain:1
Jul 26, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 449 of the SLC29A3 protein (p.Thr449Met). This variant is present in population databases (rs267607058, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with SLC29A3-related conditions. ClinVar contains an entry for this variant (Variation ID: 1443470). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C15"). This variant disrupts the p.Thr449 amino acid residue in SLC29A3. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 19336477, 20595384, 22875837). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.24
BayesDel_addAF
Uncertain
0.025
T
BayesDel_noAF
Uncertain
0.090
CADD
Pathogenic
29
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.089
T;T;.
Eigen
Pathogenic
0.78
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.92
.;D;D
M_CAP
Uncertain
0.18
D
MetaRNN
Pathogenic
0.85
D;D;D
MetaSVM
Uncertain
-0.027
T
MutationAssessor
Uncertain
2.4
M;M;.
PhyloP100
7.9
PrimateAI
Uncertain
0.57
T
PROVEAN
Uncertain
-2.6
.;D;.
REVEL
Uncertain
0.41
Sift
Uncertain
0.0020
.;D;.
Polyphen
1.0
D;D;.
Vest4
0.61
MutPred
0.82
Loss of glycosylation at T449 (P = 0.3347);Loss of glycosylation at T449 (P = 0.3347);.;
MVP
0.92
MPC
0.38
ClinPred
0.62
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
0.97
Varity_R
0.60
gMVP
0.83

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: rs267607058; hg19: chr10-73122283; COSMIC: COSV64384540; COSMIC: COSV64384540; API