21-36896944-T-C

Position:

chr21-36896944-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2PP3_StrongPP5

The NM_001352514.2(HLCS):c.1808A>G(p.Tyr603Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000105 in 1,614,070 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

HLCS
NM_001352514.2 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:1

Conservation

PhyloP100: 6.70

Variant links:

Genes affected

HLCS (HGNC:4976): (holocarboxylase synthetase) This gene encodes an enzyme that catalyzes the binding of biotin to carboxylases and histones. The protein plays an important role in gluconeogenesis, fatty acid synthesis and branched chain amino acid catabolism. Defects in this gene are the cause of holocarboxylase synthetase deficiency. Multiple alternatively spliced variants, encoding the same protein, have been identified.[provided by RefSeq, Jun 2011]

HLCS links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.945

PP5

Variant 21-36896944-T-C is Pathogenic according to our data. Variant chr21-36896944-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 554029.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=3, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HLCS	NM_001352514.2 linkuse as main transcript	c.1808A>G	p.Tyr603Cys	missense_variant	6/11	ENST00000674895.3	NP_001339443.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HLCS	ENST00000674895.3 linkuse as main transcript	c.1808A>G	p.Tyr603Cys	missense_variant	6/11		NM_001352514.2	ENSP00000502087	P4	P50747-2

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152186

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.000188

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000239

AC:

AN:

251486

Hom.:

AF XY:

0.0000294

AC XY:

AN XY:

135920

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.000139

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000958

AC:

AN:

1461884

Hom.:

Cov.:

AF XY:

0.00000688

AC XY:

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.000112

Gnomad4 NFE exome

AF:

0.00000540

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152186

Hom.:

Cov.:

AF XY:

0.0000404

AC XY:

AN XY:

74344

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.000188

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ExAC

AF:

0.0000412

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3Uncertain:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Holocarboxylase synthetase deficiency

Pathogenic:3Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 12, 2023	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Dec 06, 2022	ClinVar contains an entry for this variant (Variation ID: 554029). This missense change has been observed in individual(s) with holocarboxylase synthetase deficiency (PMID: 11735028, 17274881). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is present in population databases (rs781603756, gnomAD 0.02%). This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 456 of the HLCS protein (p.Tyr456Cys). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt HLCS protein function. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Experimental studies have shown that this missense change affects HLCS function (PMID: 11735028). -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Sep 24, 2017	- -
Likely pathogenic, criteria provided, single submitter	curation	Laboratory of Medical Genetics, National & Kapodistrian University of Athens	Feb 01, 2024	- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.73

BayesDel_addAF

Pathogenic

0.47

BayesDel_noAF

Pathogenic

0.54

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.81

D;D;D

Eigen

Uncertain

0.51

Eigen_PC

Uncertain

0.40

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.90

D;.;.

M_CAP

Uncertain

0.28

MetaRNN

Pathogenic

0.95

D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.8

M;M;M

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.58

PROVEAN

Pathogenic

-6.7

.;D;D

REVEL

Pathogenic

0.92

Sift

Pathogenic

0.0

.;D;D

Sift4G

Pathogenic

0.0010

D;D;D

Polyphen

1.0

D;D;D

Vest4

0.99

MutPred

0.74

Loss of catalytic residue at I455 (P = 0.1183);Loss of catalytic residue at I455 (P = 0.1183);Loss of catalytic residue at I455 (P = 0.1183);

MVP

0.99

MPC

0.65

ClinPred

0.73

GERP RS

5.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.78

gMVP

0.94

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