rs369588002

Variant names:

• chr10-100990470-G-A
• rs369588002
• NM_021830.5:c.1519G>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PP2 PP5 BP4

The NM_021830.5(TWNK):​c.1519G>A​(p.Val507Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000124 in 1,614,120 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: TWNK NM_021830.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:3 O:1
• Conservation: PhyloP100: 2.96
• Publications: 13 publications found

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]

MRPL43 (HGNC:14517): (mitochondrial ribosomal protein L43) Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and help in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit. They have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. Another difference between mammalian mitoribosomes and prokaryotic ribosomes is that the latter contain a 5S rRNA. Among different species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology. This gene encodes a 39S subunit protein. This gene and the gene for a semaphorin class 4 protein (SEMA4G) overlap at map location 10q24.31 and are transcribed in opposite directions. Sequence analysis identified multiple transcript variants encoding at least four different protein isoforms. [provided by RefSeq, Jul 2008]

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 36 curated pathogenic missense variants (we use a threshold of 10). The gene has 6 curated benign missense variants. Gene score misZ: 1.6071 (below the threshold of 3.09). Trascript score misZ: 2.58 (below the threshold of 3.09). GenCC associations: The gene is linked to mitochondrial DNA depletion syndrome 7 (hepatocerebral type), autosomal dominant progressive external ophthalmoplegia, progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 3, Perrault syndrome, mitochondrial DNA depletion syndrome, hepatocerebrorenal form.
• PP5: Variant 10-100990470-G-A is Pathogenic according to our data. Variant chr10-100990470-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 162051.
• BP4: Computational evidence support a benign effect (MetaRNN=0.25000972). . Strength limited to SUPPORTING due to the PP5.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_021830.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TWNK	NM_021830.5	MANE Select	c.1519G>A	p.Val507Ile	missense	Exon 3 of 5	NP_068602.2
	TWNK	NM_001163812.2		c.1519G>A	p.Val507Ile	missense	Exon 3 of 5	NP_001157284.1	Q96RR1-2
	TWNK	NM_001163813.2		c.157G>A	p.Val53Ile	missense	Exon 3 of 5	NP_001157285.1	A0A2R8Y4V4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TWNK	ENST00000311916.8	TSL:1 MANE Select	c.1519G>A	p.Val507Ile	missense	Exon 3 of 5	ENSP00000309595.2	Q96RR1-1
	TWNK	ENST00000370228.2	TSL:1	c.1519G>A	p.Val507Ile	missense	Exon 3 of 5	ENSP00000359248.1	Q96RR1-2
	TWNK	ENST00000473656.5	TSL:2	c.157G>A	p.Val53Ile	missense	Exon 3 of 5	ENSP00000494326.1	A0A2R8Y4V4

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152216 Hom.: 0 Cov.: 32

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: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000199 AC: 5 AN: 251486 AF XY: 0.0000221

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000116 AC: 17 AN: 1461786 Hom.: 0 Cov.: 31 AF XY: 0.0000138 AC XY: 10 AN XY: 727210

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.0000447 AC: 2 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.000347 AC: 2 AN: 5768

European-Non Finnish (NFE) AF: 0.00000989 AC: 11 AN: 1111938

Other (OTH) AF: 0.0000166 AC: 1 AN: 60390

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152334 Hom.: 0 Cov.: 32 AF XY: 0.0000268 AC XY: 2 AN XY: 74490

African (AFR) AF: 0.00 AC: 0 AN: 41570

American (AMR) AF: 0.0000653 AC: 1 AN: 15308

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5188

South Asian (SAS) AF: 0.000414 AC: 2 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
1	2	-	not provided (3)
-	1	-	not specified (1)
1	-	-	Perrault syndrome 5 (1)
-	-	-	Perrault syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.091
BayesDel_addAF	Benign	-0.14	T
BayesDel_noAF	Benign	-0.24
CADD	Benign	21
DANN	Uncertain	0.98
DEOGEN2	Benign	0.37	T
Eigen	Benign	-0.15
Eigen_PC	Benign	-0.018
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Benign	0.84	T
M_CAP	Uncertain	0.17	D
MetaRNN	Benign	0.25	T
MetaSVM	Uncertain	0.016	D
MutationAssessor	Uncertain	2.1	M
PhyloP100		3.0
PROVEAN	Benign	-0.59	N
REVEL	Pathogenic	0.72
Sift	Benign	0.13	T
Sift4G	Uncertain	0.039	D
Polyphen		0.64	P
Vest4		0.70
MVP		0.41
MPC		0.59
ClinPred		0.25	T
GERP RS		4.8
Varity_R		0.045
gMVP		0.33
Mutation Taster		=37/63	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

Other links and lift over

dbSNP: rs369588002; hg19: chr10-102750227; COSMIC: COSV52966985; COSMIC: COSV52966985;