chr21-36896944-T-C

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

HLCS
NM_001352514.2 missense

Scores

11
7
1

Clinical Significance

Likely pathogenic criteria provided, multiple submitters, no conflicts P:4U:1

Conservation

PhyloP100: 6.70

Publications

2 publications found
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 Gene-Disease associations (from GenCC):
  • holocarboxylase synthetase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Myriad Women’s Health, Orphanet, Labcorp Genetics (formerly Invitae), G2P, ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 14 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 Likely_pathogenic. ClinVar VariationId is 554029.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HLCSNM_001352514.2 linkc.1808A>G p.Tyr603Cys missense_variant Exon 6 of 11 ENST00000674895.3 NP_001339443.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HLCSENST00000674895.3 linkc.1808A>G p.Tyr603Cys missense_variant Exon 6 of 11 NM_001352514.2 ENSP00000502087.2 P50747-2A0A8C8QSB1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152186
Hom.:
0
Cov.:
32
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
GnomAD2 exomes
AF:
0.0000239
AC:
6
AN:
251486
AF XY:
0.0000294
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 FIN exome
AF:
0.000139
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000958
AC:
14
AN:
1461884
Hom.:
0
Cov.:
31
AF XY:
0.00000688
AC XY:
5
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.000112
AC:
6
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1112002
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.471
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152186
Hom.:
0
Cov.:
32
AF XY:
0.0000404
AC XY:
3
AN XY:
74344
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.000188
AC:
2
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.442
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00000772
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000412
AC:
5

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:4Uncertain:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Holocarboxylase synthetase deficiency Pathogenic:4Uncertain:1
Dec 06, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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). This variant is present in population databases (rs781603756, gnomAD 0.02%). 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. ClinVar contains an entry for this variant (Variation ID: 554029). 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. Experimental studies have shown that this missense change affects HLCS function (PMID: 11735028). 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. -

Sep 24, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Jun 01, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 12, 2023
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 01, 2024
Laboratory of Medical Genetics, National & Kapodistrian University of Athens
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.73
BayesDel_addAF
Pathogenic
0.47
D
BayesDel_noAF
Pathogenic
0.54
CADD
Pathogenic
28
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
D
LIST_S2
Uncertain
0.90
D;.;.
M_CAP
Uncertain
0.28
D
MetaRNN
Pathogenic
0.95
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.8
M;M;M
PhyloP100
6.7
PrimateAI
Uncertain
0.58
T
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
D
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.78
gMVP
0.94
Mutation Taster
=2/98
disease causing

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

Other links and lift over

dbSNP: rs781603756; hg19: chr21-38269244; API