22-50579248-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_005198.5(CHKB):c.1121C>T(p.Ala374Val) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,370 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: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

CHKB
NM_005198.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.77

Variant links:

Genes affected

CHKB (HGNC:1938): (choline kinase beta) Choline kinase (CK) and ethanolamine kinase (EK) catalyze the phosphorylation of choline/ethanolamine to phosphocholine/phosphoethanolamine. This is the first enzyme in the biosynthesis of phosphatidylcholine/phosphatidylethanolamine in all animal cells. The highly purified CKs from mammalian sources and their recombinant gene products have been shown to have EK activity also, indicating that both activities reside on the same protein. The choline kinase-like protein encoded by CHKL belongs to the choline/ethanolamine kinase family; however, its exact function is not known. Read-through transcripts are expressed from this locus that include exons from the downstream CPT1B locus. [provided by RefSeq, Jun 2009]

CHKB links:

CHKB-CPT1B (HGNC:):

CHKB-CPT1B links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.907

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHKB	NM_005198.5 linkuse as main transcript	c.1121C>T	p.Ala374Val	missense_variant	11/11	ENST00000406938.3
CHKB-CPT1B	NR_027928.2 linkuse as main transcript	n.1339C>T		non_coding_transcript_exon_variant	11/30

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHKB	ENST00000406938.3 linkuse as main transcript	c.1121C>T	p.Ala374Val	missense_variant	11/11	1	NM_005198.5	P1	Q9Y259-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000405

AC:

AN:

247166

Hom.:

AF XY:

0.00000746

AC XY:

AN XY:

134106

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:

0.00000908

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461370

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

726922

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:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

ExAC

AF:

0.00000824

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Megaconial type congenital muscular dystrophy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 04, 2019

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with CHKB-related conditions. This variant is present in population databases (rs751958642, ExAC 0.002%). This sequence change replaces alanine with valine at codon 374 of the CHKB protein (p.Ala374Val). The alanine residue is moderately conserved and there is a small physicochemical difference between alanine and valine. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.96

BayesDel_addAF

Pathogenic

0.23

BayesDel_noAF

Uncertain

0.10

Cadd

Pathogenic

Dann

Uncertain

1.0

DEOGEN2

Uncertain

0.61

Eigen

Pathogenic

0.82

Eigen_PC

Pathogenic

0.71

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Pathogenic

0.99

M_CAP

Pathogenic

0.37

MetaRNN

Pathogenic

0.91

MetaSVM

Uncertain

0.36

MutationAssessor

Pathogenic

3.8

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.61

PROVEAN

Uncertain

-3.2

REVEL

Pathogenic

0.74

Sift

Uncertain

0.0020

Sift4G

Uncertain

0.0040

Polyphen

1.0

Vest4

0.60

MutPred

0.80

Loss of helix (P = 0.2022);

MVP

0.90

ClinPred

0.99

GERP RS

4.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.75

gMVP

0.66

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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