NM_005198.5:c.275C>T

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2BP4_ModerateBS1_Supporting

The NM_005198.5(CHKB):c.275C>T(p.Pro92Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000102 in 1,591,840 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00027 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000084 ( 0 hom. )

Consequence

CHKB
NM_005198.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 1.24

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:41998): (CHKB-CPT1B readthrough (NMD candidate)) The genes CHKB and CPT1B are adjacent on chromosome 22 and read-through transcripts are expressed that include exons from both loci. The read-through transcripts are candidates for nonsense-mediated mRNA decay (NMD) and are unlikely to express proteins. [provided by RefSeq, Jun 2009]

CHKB-CPT1B links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.15244907).

BS1

Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.000269 (41/152308) while in subpopulation AMR AF= 0.00157 (24/15310). AF 95% confidence interval is 0.00108. There are 0 homozygotes in gnomad4. There are 23 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHKB	NM_005198.5 link	c.275C>T	p.Pro92Leu	missense_variant	Exon 2 of 11	ENST00000406938.3	NP_005189.2	Q9Y259-1A0A024R4X4
CHKB-CPT1B	NR_027928.2 link	n.493C>T		non_coding_transcript_exon_variant	Exon 2 of 30

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHKB	ENST00000406938.3 link	c.275C>T	p.Pro92Leu	missense_variant	Exon 2 of 11	1	NM_005198.5	ENSP00000384400.3		Q9Y259-1

Frequencies

GnomAD3 genomes

AF:

0.000269

AC:

AN:

152190

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000724

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00157

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:

0.000191

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.000119

AC:

AN:

209868

Hom.:

AF XY:

0.0000877

AC XY:

AN XY:

113992

show subpopulations

Gnomad AFR exome

AF:

0.0000781

Gnomad AMR exome

AF:

0.000259

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:

0.000174

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000841

AC:

121

AN:

1439532

Hom.:

Cov.:

AF XY:

0.0000952

AC XY:

AN XY:

714134

show subpopulations

Gnomad4 AFR exome

AF:

0.0000604

Gnomad4 AMR exome

AF:

0.000287

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:

0.0000942

Gnomad4 OTH exome

AF:

0.0000505

GnomAD4 genome

AF:

0.000269

AC:

AN:

152308

Hom.:

Cov.:

AF XY:

0.000309

AC XY:

AN XY:

74484

show subpopulations

Gnomad4 AFR

AF:

0.0000721

Gnomad4 AMR

AF:

0.00157

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000191

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000116

Hom.:

Bravo

AF:

0.000170

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000350

AC:

ExAC

AF:

0.000100

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Megaconial type congenital muscular dystrophy

Uncertain:2

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Oct 13, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 92 of the CHKB protein (p.Pro92Leu). This variant is present in population databases (rs140867913, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with CHKB-related conditions. ClinVar contains an entry for this variant (Variation ID: 342175). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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. -

Inborn genetic diseases

Uncertain:1

Feb 22, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.275C>T (p.P92L) alteration is located in exon 2 (coding exon 2) of the CHKB gene. This alteration results from a C to T substitution at nucleotide position 275, causing the proline (P) at amino acid position 92 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Oct 28, 2016

Eurofins Ntd Llc (ga)

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.081

BayesDel_addAF

Benign

-0.36

BayesDel_noAF

Benign

-0.46

CADD

Benign

DANN

Uncertain

0.98

DEOGEN2

Uncertain

0.50

Eigen

Benign

-0.33

Eigen_PC

Benign

-0.26

FATHMM_MKL

Benign

0.29

LIST_S2

Benign

0.81

M_CAP

Pathogenic

0.37

MetaRNN

Benign

0.15

MetaSVM

Benign

-1.1

MutationAssessor

Benign

1.7

PrimateAI

Uncertain

0.69

PROVEAN

Uncertain

-2.4

REVEL

Benign

0.087

Sift

Benign

0.21

Sift4G

Benign

0.17

Polyphen

0.64

Vest4

0.19

MVP

0.81

ClinPred

0.069

GERP RS

3.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.17

gMVP

0.54

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