rs137852870

Variant summary

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

The NM_000709.4(BCKDHA):​c.1312T>A​(p.Tyr438Asn) variant causes a missense change. The variant allele was found at a frequency of 0.0000571 in 1,611,804 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 0.00012 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000051 ( 0 hom. )

Consequence

BCKDHA
NM_000709.4 missense

Scores

12
5
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:19O:1

Conservation

PhyloP100: 5.59
Variant links:
Genes affected
BCKDHA (HGNC:986): (branched chain keto acid dehydrogenase E1 subunit alpha) The branched-chain alpha-keto acid (BCAA) dehydrogenase (BCKD) complex is an innter mitochondrial enzyme complex that catalyzes the second major step in the catabolism of the branched-chain amino acids leucine, isoleucine, and valine. The BCKD complex consists of three catalytic components: a heterotetrameric (alpha2-beta2) branched-chain alpha-keto acid decarboxylase (E1), a dihydrolipoyl transacylase (E2), and a dihydrolipoamide dehydrogenase (E3). This gene encodes the alpha subunit of the decarboxylase (E1) component. Mutations in this gene result in maple syrup urine disease, type IA. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Sep 2009]

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, 0.981
PP5
Variant 19-41424582-T-A is Pathogenic according to our data. Variant chr19-41424582-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 100009.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-41424582-T-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BCKDHANM_000709.4 linkc.1312T>A p.Tyr438Asn missense_variant Exon 9 of 9 ENST00000269980.7 NP_000700.1 P12694-1A0A024R0K3
BCKDHANM_001164783.2 linkc.1309T>A p.Tyr437Asn missense_variant Exon 9 of 9 NP_001158255.1 P12694Q59EI3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BCKDHAENST00000269980.7 linkc.1312T>A p.Tyr438Asn missense_variant Exon 9 of 9 1 NM_000709.4 ENSP00000269980.2 P12694-1
ENSG00000255730ENST00000540732.3 linkc.1414T>A p.Tyr472Asn missense_variant Exon 10 of 10 2 ENSP00000443246.1 F5H5P2
BCKDHAENST00000457836.6 linkc.1321T>A p.Tyr441Asn missense_variant Exon 9 of 9 2 ENSP00000416000.2 P12694-2
BCKDHAENST00000544905.1 linkc.141T>A p.Thr47Thr synonymous_variant Exon 2 of 2 2 ENSP00000445727.1 H0YH20

Frequencies

GnomAD3 genomes
AF:
0.000118
AC:
18
AN:
152154
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:
0.000265
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000643
AC:
16
AN:
248834
Hom.:
0
AF XY:
0.0000521
AC XY:
7
AN XY:
134482
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000143
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000507
AC:
74
AN:
1459650
Hom.:
0
Cov.:
35
AF XY:
0.0000524
AC XY:
38
AN XY:
725838
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.0000375
Gnomad4 NFE exome
AF:
0.0000612
Gnomad4 OTH exome
AF:
0.0000498
GnomAD4 genome
AF:
0.000118
AC:
18
AN:
152154
Hom.:
0
Cov.:
32
AF XY:
0.000135
AC XY:
10
AN XY:
74312
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:
0.000265
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000142
Hom.:
0
Bravo
AF:
0.0000831
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000494
AC:
6

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:19Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Maple syrup urine disease Pathogenic:10Other:1
-
GeneReviews
Significance: not provided
Review Status: no classification provided
Collection Method: literature only

- -

Aug 15, 2003
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

-
UNC Molecular Genetics Laboratory, University of North Carolina at Chapel Hill
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

The BCKDHA c.1312T>A (p.Y438N) variant (also called Y393N) is a pathogenic founder variant associated with maple syrup urine disease (MSUD) in the Old Order Mennonite population. The p.Y438N variant has been associated with classical MSUD in a homozygous state, and in non-Mennonite individuals in a compound heterozygous state. This variant has been shown to destabilize the E1 catalytic subunit of the branched-chain alpha-keto acid dehydrogenase complex and was associated with very low enzyme activity (PMID: 1885764; 2241958; 2703538; 11825067; 26830710). -

Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jan 24, 2017
Counsyl
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 16, 2020
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was classified as: Likely pathogenic. The following ACMG criteria were applied in classifying this variant: PS1,PS3,PM2,PP3. -

May 31, 2018
SIB Swiss Institute of Bioinformatics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: curation

This variant is interpreted as a Likely Pathogenic, for Maple syrup urine disease, in Autosomal Recessive manner. The following ACMG Tag(s) were applied: PM2 => Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium. PP3 => Multiple lines of computational evidence support a deleterious effect on the gene or gene product. PS3 => Well-established functional studies show a deleterious effect (PMID:1885764). -

Oct 28, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with asparagine, which is neutral and polar, at codon 438 of the BCKDHA protein (p.Tyr438Asn). This variant is present in population databases (rs137852870, gnomAD 0.02%). This missense change has been observed in individual(s) with maple syrup urine disease (PMID: 2703538, 11825067, 12888983, 20136525, 26830710, 28170084). It has also been observed to segregate with disease in related individuals. This variant is also known as Y393N. ClinVar contains an entry for this variant (Variation ID: 100009). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt BCKDHA protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects BCKDHA function (PMID: 1885764). For these reasons, this variant has been classified as Pathogenic. -

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

The missense variant c.1312T>A (p.Tyr438Asn) in BCKDHA gene has been observed in individual(s) with maple syrup urine disease (Latisha D Love-Gregory et.al.,2002). Experimental studies have shown that this missense change affects BCKDHA function (Stojiljkovic M et.al 2016). This variant has been reported to the ClinVar database as Pathogenic/Likely_pathogenic. The p.Tyr438Asn variant is reported with allele frequency 0.007% in gnomAD exomes and novel in 1000 Genomes. The amino acid Tyr at position 438 is changed to a Asn changing protein sequence and it might alter its composition and physico-chemical properties. For these reasons, this variant has been classified as Pathogenic . -

Sep 22, 2021
Revvity Omics, Revvity
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Nov 07, 2021
Genome-Nilou Lab
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Maple syrup urine disease type 1A Pathogenic:5
Oct 05, 2015
Genetic Services Laboratory, University of Chicago
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 30, 2024
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jan 06, 2017
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: The BCKDHA c.1312T>A (p.Tyr438Asn) variant involves the alteration of a conserved nucleotide. 5/5 in silico tools predict a damaging outcome for this substitution. This variant was found in 6/119260 control chromosomes at a frequency of 0.0000503, which does not exceed the estimated maximal expected allele frequency of a pathogenic BCKDHA variant (0.0016771). It was reported in several MSUD patients in either homozygosity or in compound heterozygosity with other disease causing variants indicating pathogenicity. Moreover, the c.1312T>A is considered to be a founder mutation in certain Mennonite populations (GeneReviews). In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant is classified as pathogenic. -

Sep 16, 2020
Natera, Inc.
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Mar 05, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Pathogenic:3
Aug 13, 2012
Eurofins Ntd Llc (ga)
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jul 05, 2017
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 31, 2023
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Published functional studies found this variant is associated with significantly reduced enzyme activity (Fisher CR et al., 1991); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Also known as p.(Y393N); This variant is associated with the following publications: (PMID: 14517957, 26830710, 11825067, 24268812, 21228398, 25087612, 19456321, 19715473, 11486905, 18378174, 21844576, 12888983, 7707687, 16468966, 2703538, 28170084, 31028937, 31589614, 32853555, 25255367, 22593002, 33996492, 32812330, 31980395, 1867199, 2241958, 1885764) -

Inborn genetic diseases Pathogenic:1
Aug 25, 2021
Ambry Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.1312T>A (p.Y438N) alteration is located in exon 9 (coding exon 9) of the BCKDHA gene. This alteration results from a T to A substitution at nucleotide position 1312, causing the tyrosine (Y) at amino acid position 438 to be replaced by an asparagine (N). Based on data from gnomAD, the A allele has an overall frequency of 0.01% (21/280202) total alleles studied. The highest observed frequency was 0.02% (21/127306) of European (non-Finnish) alleles. This mutation, also referred to as Y393N in the literature, has been reported in the homozygous state in several patients with maple syrup urine disease and is a founder mutation with an estimated carrier frequency of approximately 8% in the Old Order Mennonite population (Fisher, 1991a; Puffenberger, 2003; Khalifa, 2020). In vitro functional studies demonstrated that this mutation impedes assembly of the E1α and E1β subunits (Fisher, 1991b). This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Pathogenic
0.36
D
BayesDel_noAF
Pathogenic
0.53
CADD
Pathogenic
27
DANN
Uncertain
0.99
DEOGEN2
Benign
0.33
.;T;.
Eigen
Pathogenic
0.75
Eigen_PC
Uncertain
0.66
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.95
D;D;D
M_CAP
Pathogenic
0.91
D
MetaRNN
Pathogenic
0.98
D;D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
3.7
.;H;.
PrimateAI
Uncertain
0.69
T
PROVEAN
Pathogenic
-8.4
D;D;D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0
D;D;D
Polyphen
1.0
.;D;.
Vest4
0.93
MVP
0.95
MPC
0.48
ClinPred
0.99
D
GERP RS
5.5
Varity_R
0.97
gMVP
0.95

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: rs137852870; hg19: chr19-41930487; API