chr22-50582642-C-T

Position:

chr22-50582642-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_005198.5(CHKB):c.140G>A(p.Arg47His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000869 in 1,610,830 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

CHKB
NM_005198.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.0140

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 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.10190734).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHKB	NM_005198.5 linkuse as main transcript	c.140G>A	p.Arg47His	missense_variant	1/11	ENST00000406938.3	NP_005189.2
CHKB-CPT1B	NR_027928.2 linkuse as main transcript	n.358G>A		non_coding_transcript_exon_variant	1/30

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHKB	ENST00000406938.3 linkuse as main transcript	c.140G>A	p.Arg47His	missense_variant	1/11	1	NM_005198.5	ENSP00000384400	P1	Q9Y259-1

Frequencies

GnomAD3 genomes

AF:

0.0000591

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000217

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000174

AC:

AN:

230024

Hom.:

AF XY:

0.0000157

AC XY:

AN XY:

127480

show subpopulations

Gnomad AFR exome

AF:

0.000297

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000343

AC:

AN:

1458502

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

725576

show subpopulations

Gnomad4 AFR exome

AF:

0.000150

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:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000591

AC:

AN:

152328

Hom.:

Cov.:

AF XY:

0.0000537

AC XY:

AN XY:

74484

show subpopulations

Gnomad4 AFR

AF:

0.000216

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:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000529

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

Labcorp Genetics (formerly Invitae), Labcorp

Feb 07, 2018

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 output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The histidine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with CHKB-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces arginine with histidine at codon 47 of the CHKB protein (p.Arg47His). The arginine residue is weakly conserved and there is a small physicochemical difference between arginine and histidine. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.083

BayesDel_addAF

Benign

-0.33

BayesDel_noAF

Benign

-0.41

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.10

Eigen

Benign

-0.26

Eigen_PC

Benign

-0.094

FATHMM_MKL

Benign

0.25

LIST_S2

Benign

0.63

M_CAP

Pathogenic

0.34

MetaRNN

Benign

0.10

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.90

MutationTaster

Benign

0.99

PrimateAI

Uncertain

0.76

PROVEAN

Benign

-0.59

REVEL

Benign

0.069

Sift

Benign

0.090

Sift4G

Benign

0.16

Polyphen

0.056

Vest4

0.21

MVP

0.68

ClinPred

0.15

GERP RS

2.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.098

gMVP

0.31

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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