NM_001918.5:c.294C>G

Variant names:

• chr1-100230872-G-C
• rs121965001
• NM_001918.5:c.294C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1 PM2 PP3_Moderate PP5

The NM_001918.5(DBT):​c.294C>G​(p.Ile98Met) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I98V) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: DBT NM_001918.5 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 3.62
• Publications: 2 publications found

Genes affected

DBT (HGNC:2698): (dihydrolipoamide branched chain transacylase E2) The branched-chain alpha-keto acid dehydrogenase complex (BCKD) is an inner-mitochondrial enzyme complex involved in the breakdown of the branched-chain amino acids isoleucine, leucine, and valine. The BCKD complex is thought to be composed of a core of 24 transacylase (E2) subunits, and associated decarboxylase (E1), dehydrogenase (E3), and regulatory subunits. This gene encodes the transacylase (E2) subunit. Mutations in this gene result in maple syrup urine disease, type 2. Alternatively spliced transcript variants have been described, but their biological validity has not been determined. [provided by RefSeq, Jul 2008]

DBT Gene-Disease associations (from GenCC):

• maple syrup urine disease

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Labcorp Genetics (formerly Invitae)
• maple syrup urine disease type 2

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P, Myriad Women’s Health
• 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

ENSG00000285530 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PM1: In a domain Lipoyl-binding (size 75) in uniprot entity ODB2_HUMAN there are 10 pathogenic changes around while only 0 benign (100%) in NM_001918.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.858
• PP5: Variant 1-100230872-G-C is Pathogenic according to our data. Variant chr1-100230872-G-C is described in ClinVar as Pathogenic. ClinVar VariationId is 11948.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001918.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DBT	NM_001918.5	MANE Select	c.294C>G	p.Ile98Met	missense	Exon 4 of 11	NP_001909.4	P11182
	DBT	NM_001399969.1		c.-250C>G		5_prime_UTR_premature_start_codon_gain	Exon 5 of 12	NP_001386898.1	A0A7P0T9W1
	DBT	NM_001399972.1		c.-250C>G		5_prime_UTR_premature_start_codon_gain	Exon 5 of 12	NP_001386901.1	A0A7P0T9W1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DBT	ENST00000370132.8	TSL:1 MANE Select	c.294C>G	p.Ile98Met	missense	Exon 4 of 11	ENSP00000359151.3	P11182
	DBT	ENST00000370131.3	TSL:1	c.294C>G	p.Ile98Met	missense	Exon 4 of 8	ENSP00000359150.3	Q5VVL7
	DBT	ENST00000681780.1		c.-250C>G		5_prime_UTR_premature_start_codon_gain	Exon 5 of 12	ENSP00000505780.1	A0A7P0T9W1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Maple syrup urine disease type 2 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.65
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.070
CADD	Uncertain	25
DANN	Uncertain	1.0
Eigen	Pathogenic	0.72
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Benign	0.028	D
MetaRNN	Pathogenic	0.86	D
MetaSVM	Benign	-0.82	T
PhyloP100		3.6
PrimateAI	Uncertain	0.77	T
PROVEAN	Uncertain	-2.4	N
REVEL	Uncertain	0.36
Sift	Uncertain	0.0030	D
Sift4G	Uncertain	0.0030	D
Vest4		0.88
MutPred		0.77		Gain of disorder (P = 0.0498)
MVP		0.60
MPC		0.96
ClinPred		0.91	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
gMVP		0.81
Mutation Taster		=68/32	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

Other links and lift over

dbSNP: rs121965001; hg19: chr1-100696428;