MGST3

Chr 1

microsomal glutathione S-transferase 3

Also known as: GST-3, GST-III

NCBI Gene: 4259 ENSG00000143198 UniProt: O14880 OMIM: 604564

The protein catalyzes glutathione conjugation of leukotriene A4 to produce leukotriene C4 and demonstrates glutathione-dependent peroxidase activity toward lipid hydroperoxides, functioning in both cellular detoxification and synthesis of inflammatory mediators. Mutations cause autosomal recessive developmental and epileptic encephalopathy with early infantile onset. The gene shows low constraint to loss-of-function variation.

OMIM ResearchSummary from RefSeq, UniProt

This gene encodes a member of the MAPEG (Membrane Associated Proteins in Eicosanoid and Glutathione metabolism) protein family. Members of this family are involved in the production of leukotrienes and prostaglandin E, important mediators of inflammation. This gene encodes an enzyme which catalyzes the conjugation of leukotriene A4 and reduced glutathione to produce leukotriene C4. This enzyme also demonstrates glutathione-dependent peroxidase activity towards lipid hydroperoxides.[provided by RefSeq, May 2011]

OMIM ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

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P/LP missense

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LOEUF

Multiple*

Mechanism· predicted

Some data sources returned errors (1)

gnomad: Error: gnomAD API error: 400

Population Genetics & Constraint

gnomAD

Constraint data not available from gnomAD.

Background carrier burden — how many people carry a rare variant somewhere in MGST3?

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 290

197 rare PASS variants

Rare truncating (LoF)

1 in 2,900

44 rare PASS variants

Rare synonymous (reference)

1 in 1,300

63 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for MGST3. A background rate for each class, not the frequency of any particular variant; thin-coverage exons undercount.

By genetic ancestry · 9 gnomAD groups · rare = under 0.1% in that group

Group	People	Missense	Truncating
European (non-Finnish)	~556k	1 in 300	1 in 3,100
South Asian	~43k	1 in 500	1 in 3,500
Remaining (unassigned)	~30k	1 in 310	≈ 1 in 30,000
European (Finnish)	~27k	1 in 1,900	none seen
Admixed American	~22k	1 in 500	≈ 1 in 7,500
African / African American	~21k	1 in 370	1 in 1,400
East Asian	~20k	1 in 400	≈ 1 in 6,600
Ashkenazi Jewish	~13k	≈ 1 in 4,400	none seen
Middle Eastern	~2,884	1 in 240	none seen

Each group is summed over the variants that are rare in that group. Grey ≈ figures rest on fewer than five expected carriers — too few to distinguish groups. Differences mostly reflect how many people were sampled and how much variation each ancestry carries, not disease risk.

Exome coverage (gnomAD): All 5 coding exons well covered in gnomAD exomes and genomes.? see exons ↓