rs138670449

Variant summary

Our verdict is Benign. The variant received -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_183050.4(BCKDHB):​c.987C>T​(p.His329His) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000595 in 1,613,572 control chromosomes in the GnomAD database, including 10 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00046 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00061 ( 10 hom. )

Consequence

BCKDHB
NM_183050.4 synonymous

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:6

Conservation

PhyloP100: -1.03

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: Benign. The variant received -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.52).
BP6
Variant 6-80273170-C-T is Benign according to our data. Variant chr6-80273170-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 358171.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=-1.03 with no splicing effect.
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.00046 (70/152214) while in subpopulation SAS AF = 0.00829 (40/4826). AF 95% confidence interval is 0.00626. There are 0 homozygotes in GnomAd4. There are 40 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 10 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BCKDHBNM_183050.4 linkc.987C>T p.His329His synonymous_variant Exon 9 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.987C>T p.His329His synonymous_variant Exon 9 of 10 1 NM_183050.4 ENSP00000318351.5 P21953-1
BCKDHBENST00000356489.9 linkc.987C>T p.His329His synonymous_variant Exon 9 of 11 1 ENSP00000348880.5 P21953-1
BCKDHBENST00000468520.1 linkn.217C>T non_coding_transcript_exon_variant Exon 3 of 3 5

Frequencies

GnomAD3 genomes
AF:
0.000467
AC:
71
AN:
152096
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000217
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00231
Gnomad SAS
AF:
0.00849
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000132
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00131
AC:
329
AN:
250966
AF XY:
0.00157
show subpopulations
Gnomad AFR exome
AF:
0.000369
Gnomad AMR exome
AF:
0.000145
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00299
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000882
Gnomad OTH exome
AF:
0.00114
GnomAD4 exome
AF:
0.000609
AC:
890
AN:
1461358
Hom.:
10
Cov.:
30
AF XY:
0.000794
AC XY:
577
AN XY:
726974
show subpopulations
African (AFR)
AF:
0.000209
AC:
7
AN:
33460
American (AMR)
AF:
0.000134
AC:
6
AN:
44672
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26106
East Asian (EAS)
AF:
0.00209
AC:
83
AN:
39662
South Asian (SAS)
AF:
0.00741
AC:
639
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53406
Middle Eastern (MID)
AF:
0.000521
AC:
3
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000603
AC:
67
AN:
1111670
Other (OTH)
AF:
0.00141
AC:
85
AN:
60372
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.474
Heterozygous variant carriers
0
45
89
134
178
223
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.000460
AC:
70
AN:
152214
Hom.:
0
Cov.:
33
AF XY:
0.000537
AC XY:
40
AN XY:
74432
show subpopulations
African (AFR)
AF:
0.000217
AC:
9
AN:
41538
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00231
AC:
12
AN:
5190
South Asian (SAS)
AF:
0.00829
AC:
40
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000132
AC:
9
AN:
67992
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.510
Heterozygous variant carriers
0
5
10
14
19
24
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:
0.000197
Hom.:
0
Bravo
AF:
0.000306
Asia WGS
AF:
0.0120
AC:
41
AN:
3478
EpiCase
AF:
0.0000546
EpiControl
AF:
0.00

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Maple syrup urine disease Benign:3
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Dec 31, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 18, 2021
Genome-Nilou Lab
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Mar 09, 2018
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Maple syrup urine disease type 1B Benign:1
Oct 22, 2019
Natera, Inc.
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Benign:1
May 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BCKDHB: BP4, BP7, BS2 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.52
CADD
Benign
2.9
DANN
Benign
0.44
PhyloP100
-1.0
Mutation Taster
=90/10
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
Splicevardb
2.0
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: rs138670449; hg19: chr6-80982887; API