rs672601361

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1PM2PP3_StrongPP5_Moderate

The NM_021830.5(TWNK):ā€‹c.1321T>Gā€‹(p.Trp441Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,614,008 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 Pathogenic (ā˜…).

Frequency

Genomes: š‘“ 0.000013 ( 0 hom., cov: 33)
Exomes š‘“: 0.0000014 ( 0 hom. )

Consequence

TWNK
NM_021830.5 missense

Scores

10
6
2

Clinical Significance

Pathogenic criteria provided, single submitter P:2O:1

Conservation

PhyloP100: 7.99
Variant links:
Genes affected
TWNK (HGNC:1160): (twinkle mtDNA helicase) This gene encodes a hexameric DNA helicase which unwinds short stretches of double-stranded DNA in the 5' to 3' direction and, along with mitochondrial single-stranded DNA binding protein and mtDNA polymerase gamma, is thought to play a key role in mtDNA replication. The protein localizes to the mitochondrial matrix and mitochondrial nucleoids. Mutations in this gene cause infantile onset spinocerebellar ataxia (IOSCA) and progressive external ophthalmoplegia (PEO) and are also associated with several mitochondrial depletion syndromes. Alternative splicing results in multiple transcript variants encoding distinct isoforms.[provided by RefSeq, Aug 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 10 ACMG points.

PM1
In a region_of_interest Maybe required for stable oligomeric structure (size 185) in uniprot entity PEO1_HUMAN there are 13 pathogenic changes around while only 1 benign (93%) in NM_021830.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.967
PP5
Variant 10-100989721-T-G is Pathogenic according to our data. Variant chr10-100989721-T-G is described in ClinVar as [Pathogenic]. Clinvar id is 162050.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TWNKNM_021830.5 linkuse as main transcriptc.1321T>G p.Trp441Gly missense_variant 2/5 ENST00000311916.8 NP_068602.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TWNKENST00000311916.8 linkuse as main transcriptc.1321T>G p.Trp441Gly missense_variant 2/51 NM_021830.5 ENSP00000309595 P1Q96RR1-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152116
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251486
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135922
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461892
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727248
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000180
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152116
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74290
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000756
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:2Other:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Perrault syndrome 5 Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMNov 25, 2014- -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJul 10, 2023This sequence change replaces tryptophan, which is neutral and slightly polar, with glycine, which is neutral and non-polar, at codon 441 of the TWNK protein (p.Trp441Gly). This variant is present in population databases (rs672601361, gnomAD 0.0009%). This missense change has been observed in individual(s) with autosomal recessive Perrault syndrome (PMID: 25355836). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 162050). 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 TWNK protein function. For these reasons, this variant has been classified as Pathogenic. -
Perrault syndrome Other:1
not provided, no classification providedliterature onlyGeneReviews-- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.49
CADD
Pathogenic
32
DANN
Uncertain
0.98
DEOGEN2
Pathogenic
0.90
D;.
Eigen
Uncertain
0.37
Eigen_PC
Uncertain
0.49
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.97
D;D
M_CAP
Pathogenic
0.64
D
MetaRNN
Pathogenic
0.97
D;D
MetaSVM
Uncertain
0.65
D
MutationAssessor
Pathogenic
3.2
M;M
MutationTaster
Benign
1.0
D;D
PROVEAN
Pathogenic
-12
D;D
REVEL
Pathogenic
0.94
Sift
Benign
0.030
D;D
Sift4G
Uncertain
0.041
D;D
Polyphen
0.96
D;B
Vest4
0.92
MutPred
0.82
Gain of disorder (P = 0.0652);Gain of disorder (P = 0.0652);
MVP
0.95
MPC
1.6
ClinPred
1.0
D
GERP RS
5.8
Varity_R
0.89
gMVP
0.98

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.090
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs672601361; hg19: chr10-102749478; API