rs772791252

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_001352514.2(HLCS):​c.2134C>T​(p.Arg712*) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000156 in 1,607,176 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 Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. R712R) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

HLCS
NM_001352514.2 stop_gained

Scores

2
4
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:9

Conservation

PhyloP100: 4.28

Publications

5 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 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 21-36759829-G-A is Pathogenic according to our data. Variant chr21-36759829-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 426486.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.2134C>T p.Arg712* stop_gained Exon 9 of 11 ENST00000674895.3 NP_001339443.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HLCSENST00000674895.3 linkc.2134C>T p.Arg712* stop_gained Exon 9 of 11 NM_001352514.2 ENSP00000502087.2 P50747-2A0A8C8QSB1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152152
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251472
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000144
AC:
21
AN:
1455024
Hom.:
0
Cov.:
28
AF XY:
0.0000138
AC XY:
10
AN XY:
724316
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33340
American (AMR)
AF:
0.00
AC:
0
AN:
44714
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26100
East Asian (EAS)
AF:
0.0000757
AC:
3
AN:
39654
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86128
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53406
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5750
European-Non Finnish (NFE)
AF:
0.0000127
AC:
14
AN:
1105764
Other (OTH)
AF:
0.0000332
AC:
2
AN:
60168
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.444
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.0000263
AC:
4
AN:
152152
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74318
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41426
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
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:
0.0000752
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Holocarboxylase synthetase deficiency Pathogenic:8
Feb 01, 2024
Laboratory of Medical Genetics, National & Kapodistrian University of Athens
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Jan 16, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 18, 2017
Counsyl
Significance:Pathogenic
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. -

Jan 31, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 03, 2018
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: HLCS c.1693C>T (p.Arg565X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 2e-05 in 246268 control chromosomes. c.1693C>T has been reported in the literature in individuals affected with Holocarboxylase Synthetase Deficiency (Sakamoto 1998, Tang 2003, Donti 2016). These data indicate that the variant may be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in 10%-<30% of normal activity (Sakamoto_1998). One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation, and classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Oct 06, 2021
Revvity Omics, Revvity
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 12, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 426486). This premature translational stop signal has been observed in individual(s) with holocarboxylase synthetase deficiency (PMID: 9870216). This variant is present in population databases (rs772791252, gnomAD 0.007%). This sequence change creates a premature translational stop signal (p.Arg565*) in the HLCS gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in HLCS are known to be pathogenic (PMID: 16134170). -

Oct 30, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Pathogenic:1
Apr 14, 2017
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The R565X nonsense variant in the HLCS gene has been reported previously in association with holocarboxylase synthetase deciency in several unrelated individuals who were heterozygous for R565X and another variant in the HLCS gene (Sakamoto et al., 1998; Tang et al., 2003; Donti et al., 2016). This pathogenic variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.47
CADD
Pathogenic
53
DANN
Uncertain
1.0
Eigen
Uncertain
0.56
Eigen_PC
Uncertain
0.42
FATHMM_MKL
Uncertain
0.79
D
PhyloP100
4.3
Vest4
0.94
GERP RS
3.5
Mutation Taster
=2/198
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.14
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: rs772791252; hg19: chr21-38132130; COSMIC: COSV60794640; API