rs398123489

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000709.4(BCKDHA):​c.117delC​(p.Arg40GlyfsTer23) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000018 in 1,613,326 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. P39P) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000079 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

BCKDHA
NM_000709.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:12

Conservation

PhyloP100: -3.27

Publications

10 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: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 19-41410638-AC-A is Pathogenic according to our data. Variant chr19-41410638-AC-A is described in ClinVar as Pathogenic. ClinVar VariationId is 93342.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
BCKDHANM_000709.4 linkc.117delC p.Arg40GlyfsTer23 frameshift_variant Exon 2 of 9 ENST00000269980.7 NP_000700.1 P12694-1A0A024R0K3
BCKDHANM_001164783.2 linkc.117delC p.Arg40GlyfsTer23 frameshift_variant Exon 2 of 9 NP_001158255.1 P12694Q59EI3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BCKDHAENST00000269980.7 linkc.117delC p.Arg40GlyfsTer23 frameshift_variant Exon 2 of 9 1 NM_000709.4 ENSP00000269980.2 P12694-1
ENSG00000255730ENST00000540732.3 linkc.219delC p.Arg74GlyfsTer23 frameshift_variant Exon 3 of 10 2 ENSP00000443246.1 F5H5P2

Frequencies

GnomAD3 genomes
AF:
0.0000792
AC:
12
AN:
151564
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000485
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000658
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:
0.000132
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000120
AC:
3
AN:
250846
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000882
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000116
AC:
17
AN:
1461762
Hom.:
0
Cov.:
32
AF XY:
0.0000110
AC XY:
8
AN XY:
727180
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53334
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000108
AC:
12
AN:
1111984
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
2
3
5
6
8
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:
0.0000792
AC:
12
AN:
151564
Hom.:
0
Cov.:
31
AF XY:
0.0000811
AC XY:
6
AN XY:
73946
show subpopulations
African (AFR)
AF:
0.0000485
AC:
2
AN:
41196
American (AMR)
AF:
0.0000658
AC:
1
AN:
15190
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3462
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5160
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4802
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10524
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.000132
AC:
9
AN:
67938
Other (OTH)
AF:
0.00
AC:
0
AN:
2068
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.496
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:
0.00
Hom.:
0
Bravo
AF:
0.0000567

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:12
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Maple syrup urine disease Pathogenic:6
May 01, 2009
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Jul 22, 2021
Genome-Nilou Lab
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 07, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
National Newborn Screening Laboratory, Hospital Nacional de Niños
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This is a frame-shift variant in the BCKDHA gene, where loss of function is a known mechanism of disease. This variant results in a truncated protein by creating a premature stop codon. It has been published in the literature associated with individuals with MSUD (PMID: 16786533, PMID: 25333063, PMID: 26232051). -

Aug 27, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Arg40Glyfs*23) in the BCKDHA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BCKDHA are known to be pathogenic (PMID: 16786533, 22593002). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This premature translational stop signal has been observed in individuals with maple syrup urine disease (PMID: 16786533, 25333063). ClinVar contains an entry for this variant (Variation ID: 93342). For these reasons, this variant has been classified as Pathogenic. -

Jul 08, 2022
Revvity Omics, Revvity
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Maple syrup urine disease type 1A Pathogenic:4
Sep 16, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Nov 03, 2016
Counsyl
Significance:Pathogenic
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. -

Mar 06, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 18, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: BCKDHA c.117delC (p.Arg40GlyfsX23) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 1.2e-05 in 250946 control chromosomes. c.117delC has been reported in the literature in multiple individuals affected with Maple Syrup Urine Disease Type 1A (example, Couce_2015, Fernandez_Guerra_2014, Quental_2008, Strauss_2006). These data indicate that the variant is very likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function (example, Fernandez_Guerra_2014). The most pronounced variant effect resulted in a loss of detectable levels of protein subunit E1alpha that is encoded by BCKDHA in human dermal fibroblasts from classic MSUD patients. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:2
Nov 22, 2021
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (Lek et al., 2016); This variant is associated with the following publications: (PMID: 26232051, 31980395, 16786533, 25333063, 31589614, 18378174) -

Aug 23, 2013
Eurofins Ntd Llc (ga)
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
-3.3
Mutation Taster
=12/188
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: rs398123489; hg19: chr19-41916543; COSMIC: COSV54195344; COSMIC: COSV54195344; API