rs397514436

Positions:

• chr3-15635571-G-C

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_001370658.1(BTD):​c.132G>C​(p.Glu44Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E44K) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: BTD NM_001370658.1 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 2.06

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 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr3-15635569-G-A is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.964
• PP5: Variant 3-15635571-G-C is Pathogenic according to our data. Variant chr3-15635571-G-C is described in ClinVar as [Pathogenic]. Clinvar id is 38574.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BTD	NM_001370658.1	c.132G>C	p.Glu44Asp	missense_variant	2/4	ENST00000643237.3	NP_001357587.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BTD	ENST00000643237.3	c.132G>C	p.Glu44Asp	missense_variant	2/4		NM_001370658.1	ENSP00000495254.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Jan 13, 2017

- -

Biotinidase deficiency Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 10, 2023

For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Glu64 amino acid residue in BTD. Other variant(s) that disrupt this residue have been observed in individuals with BTD-related conditions (PMID: 12359137), which suggests that this may be a clinically significant amino acid residue. 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: 38574). This missense change has been observed in individual(s) with biotinidase deficiency (PMID: 26810761; Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamic acid, which is acidic and polar, with aspartic acid, which is acidic and polar, at codon 64 of the BTD protein (p.Glu64Asp). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	.;.;D;.;.;.;.;D;.;.
Eigen	Uncertain	0.28
Eigen_PC	Benign	0.097
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Uncertain	0.94	.;D;D;.;D;.;D;D;D;D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.96	D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.0	.;.;M;.;.;.;.;.;.;.
PrimateAI	Uncertain	0.49	T
PROVEAN	Uncertain	-3.0	D;D;.;.;.;.;D;D;D;.
REVEL	Pathogenic	0.72
Sift	Pathogenic	0.0	D;D;.;.;.;.;D;D;D;.
Sift4G	Pathogenic	0.0	D;D;.;.;.;.;D;D;D;.
Polyphen		1.0	.;.;D;.;.;.;.;.;.;.
Vest4		0.90, 0.92, 0.91
MutPred		0.83		.;.;Loss of sheet (P = 0.0357);.;Loss of sheet (P = 0.0357);.;.;.;.;.;
MVP		0.98
MPC		0.36
ClinPred		0.99	D
GERP RS		1.3
Varity_R		0.72
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

Other links and lift over

dbSNP: rs397514436; hg19: chr3-15677078;