NM_001370658.1:c.697C>T

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.697C>T​(p.Pro233Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,990 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. P233L) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

BTD
NM_001370658.1 missense

Scores

9
8
2

Clinical Significance

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

Conservation

PhyloP100: 7.91

Publications

1 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 7 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;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr3-15644614-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2734452.
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, 0.991
PP5
Variant 3-15644613-C-T is Pathogenic according to our data. Variant chr3-15644613-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 25039.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.697C>T p.Pro233Ser 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.697C>T p.Pro233Ser missense_variant Exon 4 of 4 NM_001370658.1 ENSP00000495254.2 P43251-4

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152098
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:
0.000192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461892
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727248
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
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:
0.0000252
AC:
1
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
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:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
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

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:
152098
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74294
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41392
American (AMR)
AF:
0.00
AC:
0
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000192
AC:
1
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
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:
0.00
AC:
0
AN:
68014
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
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
Bravo
AF:
0.00000378

ClinVar

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

Submissions by phenotype

Biotinidase deficiency Pathogenic:4Uncertain:1
Jan 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. -

Nov 08, 2024
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.697C>T (p.Pro233Ser) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251436 control chromosomes. c.697C>T has been reported in the literature together with a pathogenic frameshift variant in a compound heterozygous individual affected with Biotinidase Deficiency (Wolf_2005). Biotinidase enzyme activity in this individual was approximately 1% of normal activity (Wolf_2005). The following publication has been ascertained in the context of this evaluation (PMID: 15776412). ClinVar contains an entry for this variant (Variation ID: 25039). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Jun 07, 2017
SingHealth Duke-NUS Institute of Precision Medicine
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:curation

- -

-
Neuberg Centre For Genomic Medicine, NCGM
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The missense variant p.P233S in BTD (NM_001281723.3) has been reported before as P253S in a patient with biotinidase deficiency in a compund heterozygous state with another frameshift variant (Wolf B et al,2005). It has been submitted to ClinVar as Pathogenic/ Variants of uncertain significance. The p.P233S variant is novel (not in any individuals) in gnomAD Exomes and is novel (not in any individuals) in 1000 Genomes. The p.P233S missense variant is predicted to be damaging by both SIFT and PolyPhen2. The proline residue at codon 233 of BTD is conserved in all mammalian species. The nucleotide c.697 in BTD is predicted conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Likely Pathogenic. -

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

This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 253 of the BTD protein (p.Pro253Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with biotinidase deficiency (PMID: 15776412). ClinVar contains an entry for this variant (Variation ID: 25039). 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.Pro253 amino acid residue in BTD. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 26810761). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.74
BayesDel_addAF
Pathogenic
0.45
D
BayesDel_noAF
Pathogenic
0.41
CADD
Benign
23
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.60
.;.;D;.;.;.;T;.
Eigen
Uncertain
0.63
Eigen_PC
Uncertain
0.50
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.89
.;D;D;.;.;D;D;D
M_CAP
Uncertain
0.16
D
MetaRNN
Pathogenic
0.99
D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.78
D
MutationAssessor
Pathogenic
3.3
.;.;M;.;.;.;.;.
PhyloP100
7.9
PrimateAI
Benign
0.46
T
PROVEAN
Pathogenic
-7.7
.;D;.;.;.;D;D;D
REVEL
Pathogenic
0.81
Sift
Uncertain
0.0010
.;D;.;.;.;D;D;D
Sift4G
Pathogenic
0.0
.;D;.;.;.;D;D;D
Polyphen
1.0
.;.;D;.;.;.;.;.
Vest4
0.96, 0.96, 0.96
MutPred
0.91
.;.;Gain of glycosylation at P253 (P = 0.1166);.;.;.;.;.;
MVP
0.98
MPC
0.42
ClinPred
1.0
D
GERP RS
5.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.95
gMVP
0.95
Mutation Taster
=0/100
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: rs397514383; hg19: chr3-15686120; API