chr6-80106694-A-T

Variant summary

Our verdict is Pathogenic. Variant got 20 ACMG points: 20P and 0B. PVS1PS1_ModeratePM2PP5_Very_Strong

The NM_183050.4(BCKDHB):​c.1A>T​(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000965 in 1,554,802 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 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000093 ( 0 hom. )

Consequence

BCKDHB
NM_183050.4 start_lost

Scores

6
3
7

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 2.22
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]

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 20 ACMG points.

PVS1
Start lost variant, no new inframe start found.
PS1
Another start lost variant in NM_183050.4 (BCKDHB) was described as [Likely_pathogenic] in ClinVar as 553562
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 6-80106694-A-T is Pathogenic according to our data. Variant chr6-80106694-A-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 551456.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
BCKDHBNM_183050.4 linkuse as main transcriptc.1A>T p.Met1? start_lost 1/10 ENST00000320393.9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
BCKDHBENST00000320393.9 linkuse as main transcriptc.1A>T p.Met1? start_lost 1/101 NM_183050.4 P1P21953-1
BCKDHBENST00000356489.9 linkuse as main transcriptc.1A>T p.Met1? start_lost 1/111 P1P21953-1
BCKDHBENST00000369760.8 linkuse as main transcriptc.1A>T p.Met1? start_lost 1/63 P21953-2

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
152000
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000129
AC:
2
AN:
155290
Hom.:
0
AF XY:
0.0000120
AC XY:
1
AN XY:
83284
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:
0.0000345
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000927
AC:
13
AN:
1402802
Hom.:
0
Cov.:
32
AF XY:
0.0000101
AC XY:
7
AN XY:
692504
show subpopulations
Gnomad4 AFR exome
AF:
0.0000314
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:
0.00
Gnomad4 NFE exome
AF:
0.0000111
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
152000
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74228
show subpopulations
Gnomad4 AFR
AF:
0.0000242
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:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000151

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Maple syrup urine disease Pathogenic:2
Likely pathogenic, criteria provided, single submitterclinical testingCounsylApr 11, 2017- -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 11, 2024This sequence change affects the initiator methionine of the BCKDHB mRNA. The next in-frame methionine is located at codon 71. This variant is present in population databases (no rsID available, gnomAD 0.004%). Disruption of the initiator codon has been observed in individual(s) with maple syrup urine disease (PMID: 26257134, 31980395; Invitae). ClinVar contains an entry for this variant (Variation ID: 551456). For these reasons, this variant has been classified as Pathogenic. -
Maple syrup urine disease type 1B Pathogenic:1
Pathogenic, criteria provided, single submitterresearchCenter for Genomic Medicine, King Faisal Specialist Hospital and Research CenterMar 17, 2024- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.35
CADD
Benign
22
DANN
Benign
0.94
DEOGEN2
Benign
0.17
.;T;T
Eigen
Benign
-0.25
Eigen_PC
Benign
-0.15
FATHMM_MKL
Benign
0.52
D
LIST_S2
Uncertain
0.90
D;.;D
M_CAP
Pathogenic
1.0
D
MetaRNN
Pathogenic
0.98
D;D;D
MetaSVM
Uncertain
0.27
D
MutationTaster
Benign
1.0
D;D;D;D
PROVEAN
Benign
-0.39
N;N;N
REVEL
Uncertain
0.60
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0
D;D;D
Polyphen
0.025
.;B;B
Vest4
0.83
MutPred
0.82
Loss of solvent accessibility (P = 0.0152);Loss of solvent accessibility (P = 0.0152);Loss of solvent accessibility (P = 0.0152);
MVP
0.93
ClinPred
1.0
D
GERP RS
4.2
Varity_R
0.96
gMVP
0.55

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs1005542482; hg19: chr6-80816411; API