LACTB

Chr 15

lactamase beta

Also known as: G24, MRPL56

NCBI Gene: 114294 ENSG00000103642 UniProt: P83111 OMIM: 608440

This gene encodes a mitochondrially-localized protein that has sequence similarity to prokaryotic beta-lactamases. Many of the residues responsible for beta-lactamase activity are not conserved in this protein, suggesting it may have a different enzymatic function. Increased expression of the related mouse gene was found to be associated with obesity. Alternative splicing results in multiple transcript variants encoding different protein isoforms. [provided by RefSeq, Dec 2013]

OMIM Research

OMIM ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

0.99

LOEUF

—

Mechanism

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Tolerant — LoF & missense variants common in population

LoF Constraint?

0.99LOEUF

pLI 0.000

Z-score 1.60

OE 0.61 (0.39–0.99)

Tolerant

Typical tolerance to LoF variation

Missense Constraint?

1.26Z-score

OE missense 0.78 (0.70–0.88)

207 obs / 264.7 exp

Tolerant

Mild missense constraint

Observed / Expected Ratios?

LoF OE?0.61 (0.39–0.99)

0≤0.351.4

Missense OE?0.78 (0.70–0.88)

0≤0.61.4

Synonymous OE?0.82

0≤1.21.6

LoF obs/exp: 12 / 19.6Missense obs/exp: 207 / 264.7Syn Z: 1.43

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

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 110

711 rare PASS variants

Rare truncating (LoF)

1 in 1,800

97 rare PASS variants

Rare synonymous (reference)

1 in 190

266 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for LACTB. 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 110	1 in 1,900
South Asian	~43k	1 in 83	1 in 1,100
Remaining (unassigned)	~30k	1 in 100	≈ 1 in 9,900
European (Finnish)	~27k	1 in 150	1 in 5,200
Admixed American	~22k	1 in 180	1 in 800
African / African American	~21k	1 in 82	1 in 2,800
East Asian	~20k	1 in 110	1 in 1,600
Ashkenazi Jewish	~13k	1 in 430	1 in 1,400
Middle Eastern	~2,884	1 in 100	≈ 1 in 2,900

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.