12-6867567-A-G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PVS1_ModeratePM2

The NM_000365.6(TPI1):​c.1A>G​(p.Met1?) variant causes a start lost change. The variant allele was found at a frequency of 0.00000682 in 1,612,156 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 34)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

TPI1
NM_000365.6 start_lost

Scores

5
8
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 3.92

Publications

3 publications found
Variant links:
Genes affected
TPI1 (HGNC:12009): (triosephosphate isomerase 1) This gene encodes an enzyme, consisting of two identical proteins, which catalyzes the isomerization of glyceraldehydes 3-phosphate (G3P) and dihydroxy-acetone phosphate (DHAP) in glycolysis and gluconeogenesis. Mutations in this gene are associated with triosephosphate isomerase deficiency. Pseudogenes have been identified on chromosomes 1, 4, 6 and 7. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Apr 2009]
TPI1 Gene-Disease associations (from GenCC):
  • triosephosphate isomerase deficiency
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PVS1
Start lost variant, next in-frame start position is after 2 pathogenic variants. Next in-frame start position is after 15 codons. Genomic position: 6867609. Lost 0.057 part of the original CDS.
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TPI1NM_000365.6 linkc.1A>G p.Met1? start_lost Exon 1 of 7 ENST00000396705.10 NP_000356.1 P60174-1V9HWK1Q53HE2
TPI1NM_001159287.1 linkc.112A>G p.Met38Val missense_variant Exon 1 of 7 NP_001152759.1 P60174-3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TPI1ENST00000396705.10 linkc.1A>G p.Met1? start_lost Exon 1 of 7 1 NM_000365.6 ENSP00000379933.4 P60174-1
TPI1ENST00000229270.8 linkc.112A>G p.Met38Val missense_variant Exon 1 of 7 1 ENSP00000229270.4 P60174-3
TPI1ENST00000613953.4 linkc.112A>G p.Met38Val missense_variant Exon 1 of 7 1 ENSP00000484435.1 P60174-3

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152162
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.00000816
AC:
2
AN:
244966
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000292
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000907
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000685
AC:
10
AN:
1459994
Hom.:
0
Cov.:
34
AF XY:
0.00000551
AC XY:
4
AN XY:
726276
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33406
American (AMR)
AF:
0.0000224
AC:
1
AN:
44620
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26106
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39672
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86142
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52448
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00000720
AC:
8
AN:
1111570
Other (OTH)
AF:
0.00
AC:
0
AN:
60268
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
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

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:
152162
Hom.:
0
Cov.:
34
AF XY:
0.0000135
AC XY:
1
AN XY:
74340
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:
41456
American (AMR)
AF:
0.0000654
AC:
1
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3462
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68012
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: 0.275
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:
0.0000312
Hom.:
0
Bravo
AF:
0.00000378
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Triosephosphate isomerase deficiency Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

not provided Uncertain:1
Apr 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. ClinVar contains an entry for this variant (Variation ID: 881405). Disruption of the initiator codon has been observed in individual(s) with features of triosephosphate isomerase deficiency (PMID: 10910933). This variant is present in population databases (rs201432576, gnomAD 0.003%). This sequence change affects the initiator methionine of the TPI1 mRNA. The next in-frame methionine is located at codon 15. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Pathogenic
0.15
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.49
T;T;.
Eigen
Uncertain
0.40
Eigen_PC
Uncertain
0.39
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.71
.;T;D
M_CAP
Pathogenic
0.77
D
MetaRNN
Uncertain
0.58
D;D;D
MetaSVM
Uncertain
0.57
D
MutationAssessor
Benign
0.0
N;N;.
PhyloP100
3.9
PROVEAN
Benign
-0.95
N;.;N
REVEL
Pathogenic
0.71
Sift
Uncertain
0.0010
D;.;D
Sift4G
Uncertain
0.016
D;D;D
Polyphen
0.96
D;D;.
Vest4
0.27
MutPred
0.56
Loss of MoRF binding (P = 0.0975);Loss of MoRF binding (P = 0.0975);.;
MVP
0.90
MPC
0.64
ClinPred
0.52
D
GERP RS
4.1
PromoterAI
-0.66
Under-expression
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.90
gMVP
0.42
Mutation Taster
=35/165
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: rs201432576; hg19: chr12-6976731; API