chr10-100989352-T-G

Position:

• chr10-100989352-T-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_021830.5(TWNK):​c.1142T>G​(p.Leu381Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TWNK NM_021830.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.98

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.977

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TWNK	NM_021830.5	c.1142T>G	p.Leu381Arg	missense_variant	1/5	ENST00000311916.8	NP_068602.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TWNK	ENST00000311916.8	c.1142T>G	p.Leu381Arg	missense_variant	1/5	1	NM_021830.5	ENSP00000309595	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.46	T;.
Eigen	Pathogenic	0.80
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.86	D;D
M_CAP	Pathogenic	0.49	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	2.9	M;M
MutationTaster	Benign	1.0	D;D
PROVEAN	Pathogenic	-5.4	D;D
REVEL	Pathogenic	0.96
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0020	D;D
Polyphen		1.0	D;D
Vest4		0.96
MutPred		0.83		Loss of sheet (P = 0.0181);Loss of sheet (P = 0.0181);
MVP		0.97
MPC		1.7
ClinPred		0.99	D
GERP RS		6.0
Varity_R		0.87
gMVP		0.99

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

LitVar

Other links and lift over

dbSNP: rs111033577; hg19: chr10-102749109;