6-80343692-C-T

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1PM2PP2PP3_StrongPP5_Very_Strong

The NM_183050.4(BCKDHB):​c.1067C>T​(p.Pro356Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,613,914 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 Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. P356P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

BCKDHB
NM_183050.4 missense

Scores

16
2
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:2U:1

Conservation

PhyloP100: 7.45

Publications

1 publications found
Variant links:
Genes affected
BCKDHB (HGNC:987): (branched chain keto acid dehydrogenase E1 subunit beta) This gene encodes the E1 beta subunit of branched-chain keto acid dehydrogenase, which is a multienzyme complex associated with the inner membrane of mitochondria. This enzyme complex functions in the catabolism of branched-chain amino acids. Mutations in this gene have been associated with maple syrup urine disease (MSUD), type 1B, a disease characterized by a maple syrup odor to the urine in addition to mental and physical retardation and feeding problems. Alternative splicing at this locus results in multiple transcript variants. [provided by RefSeq, Jan 2016]
BCKDHB Gene-Disease associations (from GenCC):
  • maple syrup urine disease type 1B
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, G2P, Myriad Women’s Health
  • maple syrup urine disease
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • 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 17 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_183050.4
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 51 curated pathogenic missense variants (we use a threshold of 10). The gene has 5 curated benign missense variants. Gene score misZ: -0.17637 (below the threshold of 3.09). Trascript score misZ: -0.0026186 (below the threshold of 3.09). GenCC associations: The gene is linked to classic maple syrup urine disease, thiamine-responsive maple syrup urine disease, intermittent maple syrup urine disease, intermediate maple syrup urine disease, maple syrup urine disease type 1B, maple syrup urine disease.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.993
PP5
Variant 6-80343692-C-T is Pathogenic according to our data. Variant chr6-80343692-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 556079.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
BCKDHBNM_183050.4 linkc.1067C>T p.Pro356Leu missense_variant Exon 10 of 10 ENST00000320393.9 NP_898871.1 P21953-1A0A140VKB3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BCKDHBENST00000320393.9 linkc.1067C>T p.Pro356Leu missense_variant Exon 10 of 10 1 NM_183050.4 ENSP00000318351.5 P21953-1
BCKDHBENST00000356489.9 linkc.1067C>T p.Pro356Leu missense_variant Exon 10 of 11 1 ENSP00000348880.5 P21953-1
BCKDHBENST00000491328.1 linkn.122C>T non_coding_transcript_exon_variant Exon 1 of 2 2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152170
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1461744
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727172
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39656
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1111942
Other (OTH)
AF:
0.00
AC:
0
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
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

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:
152170
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74348
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41442
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
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:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000227
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:2Uncertain:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Maple syrup urine disease type 1A Pathogenic:1Uncertain:1
Mar 25, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 11, 2018
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. -

Maple syrup urine disease Pathogenic:1
Feb 06, 2024
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 leucine, which is neutral and non-polar, at codon 356 of the BCKDHB protein (p.Pro356Leu). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with maple syrup urine disease (PMID: 18378174, 31980395, 33955723; Invitae). ClinVar contains an entry for this variant (Variation ID: 556079). 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 BCKDHB protein function with a positive predictive value of 80%. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.93
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.46
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.85
D;D
Eigen
Pathogenic
0.79
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Pathogenic
1.0
.;D
M_CAP
Pathogenic
0.64
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.8
H;H
PhyloP100
7.4
PrimateAI
Pathogenic
0.84
D
PROVEAN
Pathogenic
-9.4
D;D
REVEL
Pathogenic
0.90
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
D;D
Vest4
0.97
MutPred
0.93
Loss of glycosylation at S358 (P = 0.096);Loss of glycosylation at S358 (P = 0.096);
MVP
0.99
MPC
0.78
ClinPred
1.0
D
GERP RS
5.3
Varity_R
0.96
gMVP
0.92
Mutation Taster
=1/99
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
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: rs1304667430; hg19: chr6-81053409; API