Genetic Variant CKMT1B:p.Arg269Trp (chr15-43596460-C-T) – ACMG Classification: Likely_pathogenic (6 pts)

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_001375484.1(CKMT1B):c.805C>T(p.Arg269Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000294 in 1,595,962 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 0.000042 ( 0 hom., cov: 25)

Exomes 𝑓: 0.000028 ( 0 hom. )

Consequence

CKMT1B
NM_001375484.1 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.609

Variant links:

Genes affected

CKMT1B (HGNC:1995): (creatine kinase, mitochondrial 1B) Mitochondrial creatine (MtCK) kinase is responsible for the transfer of high energy phosphate from mitochondria to the cytosolic carrier, creatine. It belongs to the creatine kinase isoenzyme family. It exists as two isoenzymes, sarcomeric MtCK and ubiquitous MtCK, encoded by separate genes. Mitochondrial creatine kinase occurs in two different oligomeric forms: dimers and octamers, in contrast to the exclusively dimeric cytosolic creatine kinase isoenzymes. Many malignant cancers with poor prognosis have shown overexpression of ubiquitous mitochondrial creatine kinase; this may be related to high energy turnover and failure to eliminate cancer cells via apoptosis. Ubiquitous mitochondrial creatine kinase has 80% homology with the coding exons of sarcomeric mitochondrial creatine kinase. Two genes located near each other on chromosome 15 have been identified which encode identical mitochondrial creatine kinase proteins. [provided by RefSeq, Jul 2008]

CKMT1B links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

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, 0.965

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CKMT1B	NM_001375484.1 link	c.805C>T	p.Arg269Trp	missense_variant	Exon 6 of 9	ENST00000441322.6	NP_001362413.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CKMT1B	ENST00000441322.6 link	c.805C>T	p.Arg269Trp	missense_variant	Exon 6 of 9	1	NM_001375484.1	ENSP00000413255.2		P12532-1

Frequencies

GnomAD3 genomes

AF:

0.0000416

AC:

AN:

144350

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000202

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.000101

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000297

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000522

AC:

AN:

248928

Hom.:

AF XY:

0.0000668

AC XY:

AN XY:

134716

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000579

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000328

Gnomad FIN exome

AF:

0.000325

Gnomad NFE exome

AF:

0.0000265

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000282

AC:

AN:

1451506

Hom.:

Cov.:

AF XY:

0.0000304

AC XY:

AN XY:

722546

show subpopulations

Gnomad4 AFR exome

AF:

0.0000626

Gnomad4 AMR exome

AF:

0.0000448

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.000169

Gnomad4 NFE exome

AF:

0.0000235

Gnomad4 OTH exome

AF:

0.0000167

GnomAD4 genome

AF:

0.0000415

AC:

AN:

144456

Hom.:

Cov.:

AF XY:

0.0000427

AC XY:

AN XY:

70282

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000202

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.000101

Gnomad4 NFE

AF:

0.0000297

Gnomad4 OTH

AF:

0.00

ExAC

AF:

0.0000331

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Dec 09, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.805C>T (p.R269W) alteration is located in exon 7 (coding exon 6) of the CKMT1B gene. This alteration results from a C to T substitution at nucleotide position 805, causing the arginine (R) at amino acid position 269 to be replaced by a tryptophan (W). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Uncertain

0.092

BayesDel_noAF

Uncertain

0.070

CADD

Uncertain

DANN

Uncertain

1.0

Eigen

Benign

0.14

Eigen_PC

Benign

-0.064

FATHMM_MKL

Benign

0.26

M_CAP

Benign

0.082

MetaRNN

Pathogenic

0.96

D;D;D

MetaSVM

Benign

-0.44

PrimateAI

Pathogenic

0.83

PROVEAN

Pathogenic

-7.6

D;D;.

REVEL

Uncertain

0.55

Sift

Pathogenic

0.0

D;D;.

Sift4G

Uncertain

0.028

D;D;D

Vest4

0.93

MutPred

0.94

Loss of disorder (P = 0.0259);Loss of disorder (P = 0.0259);Loss of disorder (P = 0.0259);

MVP

0.61

MPC

2.0

ClinPred

1.0

GERP RS

1.4

gMVP

0.93

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

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over