6-80167699-C-A

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM2PP2PP3_StrongPP5

The NM_183050.4(BCKDHB):​c.365C>A​(p.Thr122Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,458,336 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T122I) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

BCKDHB
NM_183050.4 missense

Scores

13
5
1

Clinical Significance

Conflicting classifications of pathogenicity no assertion criteria provided P:1U:1

Conservation

PhyloP100: 7.55

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: Likely_pathogenic. The variant received 8 ACMG points.

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, 0.984
PP5
Variant 6-80167699-C-A is Pathogenic according to our data. Variant chr6-80167699-C-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 397609.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BCKDHBNM_183050.4 linkc.365C>A p.Thr122Asn missense_variant Exon 4 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.365C>A p.Thr122Asn missense_variant Exon 4 of 10 1 NM_183050.4 ENSP00000318351.5 P21953-1
BCKDHBENST00000356489.9 linkc.365C>A p.Thr122Asn missense_variant Exon 4 of 11 1 ENSP00000348880.5 P21953-1
BCKDHBENST00000369760.8 linkc.365C>A p.Thr122Asn missense_variant Exon 4 of 6 3 ENSP00000358775.4 P21953-2

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD4 exome
AF:
0.00000206
AC:
3
AN:
1458336
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
725714
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33374
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26120
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39662
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86136
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53400
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
0.00000271
AC:
3
AN:
1108888
Other (OTH)
AF:
0.00
AC:
0
AN:
60280
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
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
Cov.:
31

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:1
Revision: no assertion criteria provided
LINK: link

Submissions by phenotype

Maple syrup urine disease Pathogenic:1
-
Bioscientia Institut fuer Medizinische Diagnostik GmbH, Sonic Healthcare
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Maple syrup urine disease type 1A Uncertain:1
Nov 21, 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.95
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Uncertain
0.070
CADD
Pathogenic
27
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.90
.;D;D
Eigen
Pathogenic
0.95
Eigen_PC
Pathogenic
0.77
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.99
D;.;D
M_CAP
Pathogenic
0.42
D
MetaRNN
Pathogenic
0.98
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.7
H;H;H
PhyloP100
7.6
PrimateAI
Pathogenic
0.86
D
PROVEAN
Uncertain
-4.3
D;D;D
REVEL
Pathogenic
0.84
Sift
Uncertain
0.0010
D;D;D
Sift4G
Uncertain
0.0020
D;D;D
Polyphen
1.0
.;D;D
Vest4
0.92
MutPred
0.88
Gain of sheet (P = 0.1208);Gain of sheet (P = 0.1208);Gain of sheet (P = 0.1208);
MVP
1.0
MPC
0.81
ClinPred
1.0
D
GERP RS
4.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.96
gMVP
0.99
Mutation Taster
=9/91
disease causing

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: rs398124575; hg19: chr6-80877416; API