rs200137189

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PM5PP3PP5

The NM_000709.4(BCKDHA):​c.890G>A​(p.Arg297His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000452 in 1,613,968 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R297C) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000044 ( 0 hom. )

Consequence

BCKDHA
NM_000709.4 missense

Scores

17
1
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:6U:3

Conservation

PhyloP100: 9.30

Publications

2 publications found
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]
BCKDHA Gene-Disease associations (from GenCC):
  • maple syrup urine disease
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • maple syrup urine disease type 1A
    Inheritance: AR Classification: DEFINITIVE Submitted by: G2P, Myriad Women’s Health, ClinGen
  • classic maple syrup urine disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • intermediate maple syrup urine disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • intermittent maple syrup urine disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • thiamine-responsive maple syrup urine disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_000709.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr19-41422664-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 555477.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.832
PP5
Variant 19-41422665-G-A is Pathogenic according to our data. Variant chr19-41422665-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 93376.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BCKDHANM_000709.4 linkc.890G>A p.Arg297His missense_variant Exon 7 of 9 ENST00000269980.7 NP_000700.1 P12694-1A0A024R0K3
BCKDHANM_001164783.2 linkc.887G>A p.Arg296His missense_variant Exon 7 of 9 NP_001158255.1 P12694Q59EI3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BCKDHAENST00000269980.7 linkc.890G>A p.Arg297His missense_variant Exon 7 of 9 1 NM_000709.4 ENSP00000269980.2 P12694-1
ENSG00000255730ENST00000540732.3 linkc.992G>A p.Arg331His missense_variant Exon 8 of 10 2 ENSP00000443246.1 F5H5P2

Frequencies

GnomAD3 genomes
AF:
0.0000592
AC:
9
AN:
152126
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00231
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000756
AC:
19
AN:
251442
AF XY:
0.0000736
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00149
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.0000438
AC:
64
AN:
1461842
Hom.:
0
Cov.:
33
AF XY:
0.0000468
AC XY:
34
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00157
AC:
41
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53376
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000153
AC:
17
AN:
1112008
Other (OTH)
AF:
0.0000993
AC:
6
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
5
11
16
22
27
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:
0.0000592
AC:
9
AN:
152126
Hom.:
0
Cov.:
32
AF XY:
0.0000404
AC XY:
3
AN XY:
74310
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41386
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00231
AC:
8
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.464
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.000111
Hom.:
0
Bravo
AF:
0.0000642
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000906
AC:
11

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:6Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Maple syrup urine disease type 1A Pathogenic:4Uncertain:1
Mar 27, 2024
Illumina Laboratory Services, Illumina
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The BCKDHA c.890G>A p.(Arg297His) missense variant has been identified in at least two individuals with maple syrup urine disease, where the variant was found in a homozygous state (PMID: 29306928; 17922217). This variant is located in a hotspot region with two nearby P/LP variants, [p.(Asp302Ala) and p.(Gly290Arg)] (ClinVar). This variant is not observed at a significant frequency in version 2.1.1 or version 4.0.0 of the Genome Aggregation Database. Multiple lines of computational evidence suggest the variant may impact the gene or gene product. Additionally, a different amino acid substitution at the same codon [p.(Arg297Cys)] has been reported in individuals with maple syrup urine disease (PMID: 28830848; 16786533; ClinVar).This variant was identified in trans with a likely pathogenic variant in this proband with a phenotype consistent with maple syrup urine disease. Based on the available evidence, the c.890G>A p.(Arg297His) variant is classified as likely pathogenic for maple syrup urine disease. -

Jan 03, 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. -

Sep 04, 2023
3billion
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: 0.007%). Predicted Consequence/Location: Missense variant Functional studies provide supporting evidence of the variant having a damaging effect on the gene or gene product (PMID: 10745006). In silico tool predictions suggest damaging effect of the variant on gene or gene product [REVEL: 0.96 (>=0.6, sensitivity 0.68 and specificity 0.92); 3Cnet: 0.99 (>=0.6, sensitivity 0.72 and precision 0.9)]. Same nucleotide change resulting in same amino acid change (PMID: 10745006) anda different missense change at the same codon (p.Arg297Cys / PMID: 16786533) have been previously reported to be associated with BCKDHA related disorder (PMID: 10745006).The variant has been reported to be in trans with a pathogenic variant as either compound heterozygous or homozygous in at least one similarly affected unrelated individual (PMID: 17922217). Therefore, this variant is classified as Likely pathogenic according to the recommendation of ACMG/AMP guideline. -

Mar 14, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 26, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Maple syrup urine disease Pathogenic:2Uncertain:1
Jun 16, 2023
Revvity Omics, Revvity
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 18, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 297 of the BCKDHA protein (p.Arg297His). This variant is present in population databases (rs200137189, gnomAD 0.1%). This missense change has been observed in individuals with maple syrup urine disease (PMID: 10745006, 17922217, 29306928). ClinVar contains an entry for this variant (Variation ID: 93376). 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%. This variant disrupts the p.Arg297 amino acid residue in BCKDHA. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 16786533, 28830848). 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. -

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

- -

not provided Uncertain:1
Sep 06, 2013
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.44
D
BayesDel_noAF
Pathogenic
0.57
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.73
.;D;.;.
Eigen
Pathogenic
0.87
Eigen_PC
Pathogenic
0.77
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D;D;D;D
M_CAP
Pathogenic
0.58
D
MetaRNN
Pathogenic
0.83
D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.3
.;M;.;.
PhyloP100
9.3
PrimateAI
Pathogenic
0.84
D
PROVEAN
Pathogenic
-5.0
D;D;D;D
REVEL
Pathogenic
0.96
Sift
Pathogenic
0.0
D;D;D;D
Sift4G
Pathogenic
0.0
D;D;D;D
Polyphen
1.0
.;D;.;.
Vest4
0.97
MVP
0.97
MPC
2.1
ClinPred
0.83
D
GERP RS
5.7
PromoterAI
0.012
Neutral
Varity_R
0.97
gMVP
0.81
Mutation Taster
=1/99
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs200137189; hg19: chr19-41928570; COSMIC: COSV54197375; COSMIC: COSV54197375; API