rs397514419

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1PM2PP2PP3_Strong

The NM_001370658.1(BTD):​c.1292G>A​(p.Gly431Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,882 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G431V) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

BTD
NM_001370658.1 missense

Scores

9
8
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 9.92

Publications

5 publications found
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]
BTD Gene-Disease associations (from GenCC):
  • biotinidase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Myriad Women’s Health, ClinGen, Orphanet, Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
  • Leigh syndrome
    Inheritance: AR Classification: MODERATE Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

PM1
In a hotspot region, there are 12 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_001370658.1
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 88 curated pathogenic missense variants (we use a threshold of 10). The gene has 9 curated benign missense variants. Gene score misZ: -0.52516 (below the threshold of 3.09). Trascript score misZ: 0.15371 (below the threshold of 3.09). GenCC associations: The gene is linked to Leigh syndrome, biotinidase deficiency.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.983

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BTDNM_001370658.1 linkc.1292G>A p.Gly431Asp 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.1292G>A p.Gly431Asp missense_variant Exon 4 of 4 NM_001370658.1 ENSP00000495254.2

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251428
AF XY:
0.0000147
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461882
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
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:
0.0000348
AC:
3
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112000
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.442
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jul 28, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: BTD c.1292G>A (p.Gly431Asp) results in a non-conservative amino acid change located in the C-terminal domain (IPR043957) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 251428 control chromosomes (i.e., 2 heterozygotes; gnomAD v2.1 Exomes dataset). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1292G>A has been reported in the literature in individuals affected with Biotinidase Deficiency (e.g., Swango_1998, Lindau-Shepard_2012, Gannavarapu_2015). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 26361991, 27625817, 9654207). One submitter has reported clinical-significance assessments for this variant to ClinVar after 2014 and has classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Biotinidase deficiency Uncertain:1
Aug 19, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 451 of the BTD protein (p.Gly451Asp). This variant is present in population databases (rs397514419, gnomAD 0.006%). 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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This missense change has been observed in individual(s) with clinical features of biotinidase deficiency (PMID: 9654207, 26361991). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.84
BayesDel_addAF
Pathogenic
0.31
D
BayesDel_noAF
Pathogenic
0.39
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.84
.;.;D;.;.;.;.
Eigen
Uncertain
0.65
Eigen_PC
Uncertain
0.66
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Benign
0.82
.;T;T;.;.;T;T
M_CAP
Uncertain
0.25
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D;D;D
MetaSVM
Uncertain
0.76
D
MutationAssessor
Pathogenic
3.1
.;.;M;.;.;.;.
PhyloP100
9.9
PrimateAI
Pathogenic
0.80
T
PROVEAN
Pathogenic
-5.7
.;D;.;.;.;D;D
REVEL
Pathogenic
0.81
Sift
Uncertain
0.0020
.;D;.;.;.;D;D
Sift4G
Uncertain
0.053
.;T;.;.;.;T;T
Polyphen
0.93
.;.;P;.;.;.;.
Vest4
0.97, 0.98, 0.98
MutPred
0.86
.;.;Gain of relative solvent accessibility (P = 0.0082);.;.;.;.;
MVP
1.0
MPC
0.35
ClinPred
0.90
D
GERP RS
5.6
Varity_R
0.80
gMVP
0.90
Mutation Taster
=0/100
disease causing (ClinVar)

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: rs397514419; hg19: chr3-15686715; COSMIC: COSV57730000; COSMIC: COSV57730000; API