5-132385444-C-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate

The NM_003060.4(SLC22A5):​c.769C>T​(p.Arg257Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000682 in 1,614,034 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R257Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000070 ( 0 hom. )

Consequence

SLC22A5
NM_003060.4 missense

Scores

7
11
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:5

Conservation

PhyloP100: 0.479

Publications

15 publications found
Variant links:
Genes affected
SLC22A5 (HGNC:10969): (solute carrier family 22 member 5) Polyspecific organic cation transporters in the liver, kidney, intestine, and other organs are critical for elimination of many endogenous small organic cations as well as a wide array of drugs and environmental toxins. The encoded protein is a plasma integral membrane protein which functions both as an organic cation transporter and as a sodium-dependent high affinity carnitine transporter. The encoded protein is involved in the active cellular uptake of carnitine. Mutations in this gene are the cause of systemic primary carnitine deficiency (CDSP), an autosomal recessive disorder manifested early in life by hypoketotic hypoglycemia and acute metabolic decompensation, and later in life by skeletal myopathy or cardiomyopathy. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Apr 2015]
SLC22A5 Gene-Disease associations (from GenCC):
  • systemic primary carnitine deficiency disease
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, ClinGen, G2P, Orphanet, PanelApp Australia, Labcorp Genetics (formerly Invitae), Myriad Women’s Health
  • short QT syndrome
    Inheritance: AR Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_003060.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.864

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SLC22A5NM_003060.4 linkc.769C>T p.Arg257Trp missense_variant Exon 4 of 10 ENST00000245407.8 NP_003051.1 O76082-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SLC22A5ENST00000245407.8 linkc.769C>T p.Arg257Trp missense_variant Exon 4 of 10 1 NM_003060.4 ENSP00000245407.3 O76082-1

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152162
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000437
AC:
11
AN:
251482
AF XY:
0.0000662
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:
0.0000967
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000698
AC:
102
AN:
1461872
Hom.:
0
Cov.:
32
AF XY:
0.0000646
AC XY:
47
AN XY:
727244
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:
0.0000116
AC:
1
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:
0.0000899
AC:
100
AN:
1111990
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.454
Heterozygous variant carriers
0
6
12
18
24
30
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000526
AC:
8
AN:
152162
Hom.:
0
Cov.:
33
AF XY:
0.0000673
AC XY:
5
AN XY:
74328
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41424
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:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.519
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000413
Hom.:
0
Bravo
AF:
0.0000416
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000906
AC:
11
EpiCase
AF:
0.00
EpiControl
AF:
0.000178

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Renal carnitine transport defect Pathogenic:1Uncertain:4
Nov 21, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 16, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Oct 03, 2022
Giacomini Lab, University of California, San Francisco
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:in vitro;research

- -

Jul 20, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 257 of the SLC22A5 protein (p.Arg257Trp). This variant is present in population databases (rs386134203, gnomAD 0.01%). This missense change has been observed in individual(s) with clinical features of carnitine deficiency (PMID: 20574985). This variant is also known as c.841C>T (p.Arg281Trp). ClinVar contains an entry for this variant (Variation ID: 25391). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt SLC22A5 protein function. Experimental studies have shown that this missense change affects SLC22A5 function (PMID: 28841266). 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. -

Mar 14, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Jun 17, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: SLC22A5 c.769C>T (p.Arg257Trp) results in a non-conservative amino acid change in the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant allele was found at a frequency of 4.4e-05 in 251482 control chromosomes, predominantly at a frequency of 9.7e-05 within the Non-Finnish European subpopulation in the gnomAD database. This frequency is not significantly higher than estimated for a pathogenic variant in SLC22A5 causing Systemic Primary Carnitine Deficiency (4.4e-05 vs 0.0046), allowing no conclusion about variant significance. c.769C>T has been observed in individual(s) affected with Systemic Primary Carnitine Deficiency (Li_2010). These data do not allow any conclusion about variant significance. At least one publication reports experimental evidence evaluating an impact on protein function (Koleske_2022, Frigeni_2017). The most pronounced variant effect results in 27% of WT carnitine transport HEK293Tcells (Koleske_2022). The following publications have been ascertained in the context of this evaluation (PMID: 28841266, 31980526, 36343260, 20574985, 25087612).ClinVar contains an entry for this variant (Variation ID: 25391). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.36
BayesDel_addAF
Uncertain
0.16
D
BayesDel_noAF
Pathogenic
0.21
CADD
Uncertain
25
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.85
D;.;.
Eigen
Uncertain
0.50
Eigen_PC
Uncertain
0.40
FATHMM_MKL
Uncertain
0.80
D
LIST_S2
Uncertain
0.96
D;D;D
M_CAP
Uncertain
0.24
D
MetaRNN
Pathogenic
0.86
D;D;D
MetaSVM
Uncertain
0.25
D
MutationAssessor
Uncertain
2.6
M;.;.
PhyloP100
0.48
PrimateAI
Uncertain
0.60
T
PROVEAN
Pathogenic
-7.5
D;D;D
REVEL
Pathogenic
0.66
Sift
Pathogenic
0.0
D;D;D
Sift4G
Uncertain
0.051
T;D;T
Polyphen
1.0
D;.;.
Vest4
0.93
MVP
0.93
MPC
0.45
ClinPred
0.77
D
GERP RS
2.8
Varity_R
0.90
gMVP
0.86
Mutation Taster
=1/99
disease causing

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: rs386134203; hg19: chr5-131721136; COSMIC: COSV99809744; COSMIC: COSV99809744; API