rs139819321

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_015087.5(SPART):​c.1309G>T​(p.Gly437Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000477 in 1,613,790 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 (★★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000047 ( 0 hom. )

Consequence

SPART
NM_015087.5 missense

Scores

10
6
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 4.38

Publications

2 publications found
Variant links:
Genes affected
SPART (HGNC:18514): (spartin) This gene encodes a protein containing a MIT (Microtubule Interacting and Trafficking molecule) domain, and is implicated in regulating endosomal trafficking and mitochondria function. The protein localizes to mitochondria and partially co-localizes with microtubules. Stimulation with epidermal growth factor (EGF) results in protein translocation to the plasma membrane, and the protein functions in the degradation and intracellular trafficking of EGF receptor. Multiple alternatively spliced variants, encoding the same protein, have been identified. Mutations associated with this gene cause autosomal recessive spastic paraplegia 20 (Troyer syndrome). [provided by RefSeq, Nov 2008]
SPART Gene-Disease associations (from GenCC):
  • Troyer syndrome
    Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.9

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SPARTNM_015087.5 linkc.1309G>T p.Gly437Cys missense_variant Exon 6 of 9 ENST00000438666.7 NP_055902.1 Q8N0X7A0A024RDV9

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SPARTENST00000438666.7 linkc.1309G>T p.Gly437Cys missense_variant Exon 6 of 9 1 NM_015087.5 ENSP00000406061.2 Q8N0X7

Frequencies

GnomAD3 genomes
AF:
0.0000527
AC:
8
AN:
151936
Hom.:
0
Cov.:
33
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:
0.000118
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000438
AC:
11
AN:
251224
AF XY:
0.0000295
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:
0.0000968
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000472
AC:
69
AN:
1461854
Hom.:
0
Cov.:
31
AF XY:
0.0000426
AC XY:
31
AN XY:
727228
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:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39690
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000585
AC:
65
AN:
1111992
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.491
Heterozygous variant carriers
0
5
10
15
20
25
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:
0.0000527
AC:
8
AN:
151936
Hom.:
0
Cov.:
33
AF XY:
0.0000270
AC XY:
2
AN XY:
74208
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41362
American (AMR)
AF:
0.00
AC:
0
AN:
15242
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4800
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10578
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000118
AC:
8
AN:
67992
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
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:
0.0000434
Hom.:
0
Bravo
AF:
0.0000604
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.0000576
AC:
7
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Jun 23, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with cysteine, which is neutral and slightly polar, at codon 437 of the SPART protein (p.Gly437Cys). This variant is present in population databases (rs139819321, gnomAD 0.008%). This variant has not been reported in the literature in individuals affected with SPART-related conditions. ClinVar contains an entry for this variant (Variation ID: 530401). 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"). 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. -

Oct 16, 2023
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Available data are insufficient to determine the clinical significance of the variant at this time. The frequency of this variant in the general population is uninformative in assessment of its pathogenicity. (http://gnomad.broadinstitute.org) Computational tools predict that this variant is damaging. -

Inborn genetic diseases Uncertain:1
Jan 04, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1309G>T (p.G437C) alteration is located in exon 6 (coding exon 5) of the SPG20 gene. This alteration results from a G to T substitution at nucleotide position 1309, causing the glycine (G) at amino acid position 437 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Hereditary spastic paraplegia Uncertain:1
Mar 01, 2019
Genome Diagnostics Laboratory, The Hospital for Sick Children
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.71
BayesDel_addAF
Pathogenic
0.32
D
BayesDel_noAF
Pathogenic
0.41
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.56
D;D;D;D;D
Eigen
Pathogenic
0.79
Eigen_PC
Pathogenic
0.77
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.95
.;.;D;.;.
M_CAP
Benign
0.082
D
MetaRNN
Pathogenic
0.90
D;D;D;D;D
MetaSVM
Pathogenic
0.86
D
PhyloP100
4.4
PrimateAI
Uncertain
0.69
T
PROVEAN
Pathogenic
-7.7
D;D;D;.;.
REVEL
Pathogenic
0.71
Sift
Uncertain
0.0020
D;D;D;.;.
Sift4G
Pathogenic
0.0
D;D;D;.;D
Polyphen
1.0
D;D;D;D;D
Vest4
0.82
MVP
0.98
MPC
0.44
ClinPred
0.92
D
GERP RS
5.8
Varity_R
0.86
gMVP
0.80
Mutation Taster
=39/61
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: rs139819321; hg19: chr13-36888538; API