GENE REFERENCE / HGNC:987

BCKDHB

branched chain keto acid dehydrogenase E1 subunit beta

protein-coding gene6q14.1Gene information

What does this gene do?

The BCKDHB gene provides instructions for making one part, the beta subunit, of a group of enzymes called the branched-chain alpha-keto acid dehydrogenase (BCKD) enzyme complex. Two beta subunits connect with two alpha subunits, which are produced from the BCKDHA gene, to form a critical piece of the enzyme complex called the E1 component.

The BCKD enzyme complex is responsible for one step in the normal breakdown of three protein building blocks (amino acids). These amino acids—leucine, isoleucine, and valine—are obtained from the diet. They are present in many kinds of food, particularly protein-rich foods such as milk, meat, and eggs. The BCKD enzyme complex is active in mitochondria, which are specialized structures inside cells that serve as energy-producing centers. The breakdown of leucine, isoleucine, and valine produces molecules that can be used for energy.

Source: MedlinePlus, National Library of Medicine. Source publication: 2025-04-03. Source review: 2008-12.

ClinGen reviews

ClinGen reviews the evidence linking a particular gene to a condition. Each rating below describes the strength of that link. It does not classify a variant in your DNA file.

Condition	Inheritance	Evidence
maple syrup urine disease type 1BMONDO:0023692 · Evaluated 2019-02-08	Autosomal recessive	DefinitiveAminoacidopathy Gene Curation Expert Panel

ClinVar records

These numbers show what has been submitted to ClinVar. They cannot tell you how likely you are to have a condition.

Submitted alleles: 907
Submissions for variants in or overlapping this gene: 1,547
Submissions explicitly reporting this gene: 1,512
Alleles reported pathogenic / likely pathogenic: 276
VariationIDs with uncertain significance: 214
VariationIDs with conflicting classifications: 29

The rows count different things: alleles, submissions or VariationIDs. Their categories can overlap, so do not add them together. Pathogenic/likely pathogenic counts exclude structural variants that merely overlap a gene. A dash in the source means “not reported,” not zero.

NCBI produces the gene-summary file each week using counts recorded at the start of the month. The numbers may differ from those on the live ClinVar website. Read the field definitions ↗

View this gene in ClinVar ↗

YOUR DNA FILE

Can your DNA file tell you about BCKDHB?

From a DNA test kit (such as 23andMe, AncestryDNA or MyHeritage). These kits check a fixed list of about 600,000 to 700,000 positions across your whole genome. ClinVar lists 276 alleles in BCKDHB reported as pathogenic or likely pathogenic. A kit checks only some of these positions, and often none of them.

From whole genome sequencing (a VCF file). Sequencing reads most of your genome. Your file lists the places where your DNA differs from the reference genome. Some regions are hard to sequence, including parts of some genes that have near-identical copies elsewhere, and a VCF file does not record which positions were read well.

If a variant is not in your file, that does not mean you don’t have it.

What BioDecode checks

BioDecode compares every variant in your file with ClinVar, on your own computer. For each match, it shows the ClinVar classification, the review status and the condition it was reported for. Your file is not uploaded.

A ClinVar classification applies to one particular variant and the condition it was reported for. It does not tell you about other variants in BCKDHB.

BioDecode cannot fill gaps in your test, diagnose a condition or replace clinical testing.

Buy BioDecode See a sample report →Check file compatibility →