rs1157567876

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_001370658.1(BTD):​c.835G>C​(p.Ala279Pro) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,614,034 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A279V) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

BTD
NM_001370658.1 missense

Scores

12
6
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 6.60

Publications

0 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: Pathogenic. The variant received 19 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 7 uncertain in NM_001370658.1
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr3-15644752-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2734454.
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, 0.963
PP5
Variant 3-15644751-G-C is Pathogenic according to our data. Variant chr3-15644751-G-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 439039.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
BTDNM_001370658.1 linkc.835G>C p.Ala279Pro 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.835G>C p.Ala279Pro 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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251396
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:
1461892
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727248
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:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00000657
AC:
1
AN:
152142
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74316
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41422
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10594
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68048
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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:
0.00
Hom.:
0

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Biotinidase deficiency Pathogenic:4
May 06, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 25, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 299 of the BTD protein (p.Ala299Pro). This variant is present in population databases (no rsID available, gnomAD 0.006%). This missense change has been observed in individual(s) with biotinidase deficiency (PMID: 26810761; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 439039). 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 with a positive predictive value of 95%. This variant disrupts the p.Ala299 amino acid residue in BTD. Other variant(s) that disrupt this residue have been observed in individuals with BTD-related conditions (PMID: 10394193), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -

Jun 24, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: BTD c.835G>C (p.Ala279Pro) results in a non-conservative amino acid change located in the Carbon-nitrogen hydrolase domain (IPR003010) of the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant allele was found at a frequency of 8e-06 in 251396 control chromosomes. c.835G>C has been observed in individual(s) affected with Biotinidase Deficiency (Procter_2016, Kannan_2023, internal data). These data indicate that the variant is likely to 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: 36684547, 26810761, 27329734). ClinVar contains an entry for this variant (Variation ID: 439039). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Nov 24, 2023
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:1
Nov 10, 2016
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.95
BayesDel_addAF
Pathogenic
0.32
D
BayesDel_noAF
Pathogenic
0.41
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.86
.;.;D;.;.;.;.
Eigen
Pathogenic
0.84
Eigen_PC
Pathogenic
0.74
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.94
.;D;D;.;.;D;D
M_CAP
Pathogenic
0.29
D
MetaRNN
Pathogenic
0.96
D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.94
D
MutationAssessor
Pathogenic
3.6
.;.;H;.;.;.;.
PhyloP100
6.6
PrimateAI
Uncertain
0.49
T
PROVEAN
Uncertain
-4.3
.;D;.;.;.;D;D
REVEL
Pathogenic
0.85
Sift
Uncertain
0.0020
.;D;.;.;.;D;D
Sift4G
Uncertain
0.0030
.;D;.;.;.;D;D
Polyphen
1.0
.;.;D;.;.;.;.
Vest4
0.94, 0.95, 0.95
MutPred
0.81
.;.;Loss of stability (P = 0.0359);.;.;.;.;
MVP
0.98
MPC
0.46
ClinPred
0.99
D
GERP RS
5.8
Varity_R
0.88
gMVP
0.99
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: rs1157567876; hg19: chr3-15686258; API