NM_001370658.1:c.1559A>G

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_001370658.1(BTD):​c.1559A>G​(p.Tyr520Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000187 in 1,607,142 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 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

BTD
NM_001370658.1 missense

Scores

14
4
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: 8.67
Variant links:
Genes affected
BTD (HGNC:1122): (biotinidase) The protein encoded by this gene functions to recycle protein-bound biotin by cleaving biocytin (biotin-epsilon-lysine), a normal product of carboxylase degradation, resulting in regeneration of free biotin. The encoded protein has also been shown to have biotinyl transferase activity. Mutations in this gene are associated with biotinidase deficiency. Multiple transcript variants encoding different isoforms have been described. [provided by RefSeq, Aug 2013]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.974
PP5
Variant 3-15645475-A-G is Pathogenic according to our data. Variant chr3-15645475-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 25101.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-15645475-A-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BTDNM_001370658.1 linkc.1559A>G p.Tyr520Cys missense_variant Exon 4 of 4 ENST00000643237.3 NP_001357587.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BTDENST00000643237.3 linkc.1559A>G p.Tyr520Cys missense_variant Exon 4 of 4 NM_001370658.1 ENSP00000495254.2 P43251-4

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152142
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000125
AC:
3
AN:
239118
Hom.:
0
AF XY:
0.0000229
AC XY:
3
AN XY:
130772
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000328
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000185
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1455000
Hom.:
0
Cov.:
32
AF XY:
0.00000276
AC XY:
2
AN XY:
723940
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
8.99e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152142
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74336
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:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378
ExAC
AF:
0.00000827
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Biotinidase deficiency Pathogenic:2
Aug 23, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The BTD c.1559A>G; p.Tyr520Cys variant (rs397514431, ClinVar Variation ID: 25101), also known as c.1619A>G; p.Tyr540Cys for NM_000060.2, is reported in the literature in an individual with biotinidase deficiency who was compound heterozygous with a second BTD variant (Norrgard 1999). This variant is only found on 3 alleles in the Genome Aggregation Database (v2.1.1), indicating it is not a common polymorphism. Computational analyses predict that this variant is deleterious (REVEL: 0.96). Based on available information, this variant is considered to be likely pathogenic. References: Norrgard KJ et al. Mutations causing profound biotinidase deficiency in children ascertained by newborn screening in the United States occur at different frequencies than in symptomatic children. Pediatr Res. 1999 Jul;46(1):20-7. PMID: 10400129. -

Aug 04, 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. 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 BTD protein function. ClinVar contains an entry for this variant (Variation ID: 25101). This missense change has been observed in individual(s) with clinical features of biotinidase deficiency (PMID: 10400129; Invitae). 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 (rs397514431, gnomAD 0.003%). This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 540 of the BTD protein (p.Tyr540Cys). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.77
BayesDel_addAF
Pathogenic
0.42
D
BayesDel_noAF
Pathogenic
0.47
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.92
.;.;D;.;.;.;.
Eigen
Pathogenic
0.87
Eigen_PC
Pathogenic
0.83
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.94
.;D;D;.;.;D;D
M_CAP
Pathogenic
0.33
D
MetaRNN
Pathogenic
0.97
D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.97
D
MutationAssessor
Pathogenic
3.1
.;.;M;.;.;.;.
PrimateAI
Uncertain
0.55
T
PROVEAN
Pathogenic
-8.2
.;D;.;.;.;D;D
REVEL
Pathogenic
0.96
Sift
Uncertain
0.0010
.;D;.;.;.;D;D
Sift4G
Pathogenic
0.0010
.;D;.;.;.;D;D
Polyphen
1.0
.;.;D;.;.;.;.
Vest4
0.93, 0.93, 0.93
MutPred
0.85
.;.;Loss of catalytic residue at L535 (P = 0.0677);.;.;.;.;
MVP
0.91
MPC
0.47
ClinPred
0.99
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.78
gMVP
0.96

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.

Other links and lift over

dbSNP: rs397514431; hg19: chr3-15686982; API