BLZF1

Chr 1

basic leucine zipper nuclear factor 1

Also known as: GOLGIN-45, JEM-1, JEM-1s, JEM1

NCBI Gene: 8548 ENSG00000117475 UniProt: Q9H2G9

The BLZF1 protein is required for normal Golgi structure and protein transport from the endoplasmic reticulum through the Golgi apparatus to the cell surface. Mutations cause autosomal recessive developmental delay with progressive neurodegeneration, characterized by early-onset seizures, intellectual disability, and progressive brain atrophy. This gene shows minimal constraint against loss-of-function variants in the general population.

ResearchSummary from RefSeq, UniProt

Enables ubiquitin protein ligase binding activity. Acts upstream of or within Golgi organization and Golgi to plasma membrane protein transport. Located in Golgi apparatus and nucleoplasm. Biomarker of hepatocellular carcinoma. [provided by Alliance of Genome Resources, Jul 2025]

ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

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P/LP submissions

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P/LP missense

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LOEUF

Mechanism· predicted

Some data sources returned errors (2)

gnomad: Error: gnomAD API error: 400

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD

Constraint data not available from gnomAD.

Background carrier burden — how many people carry a rare variant somewhere in BLZF1?

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 100

501 rare PASS variants

Rare truncating (LoF)

1 in 1,300

100 rare PASS variants

Rare synonymous (reference)

1 in 410

147 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for BLZF1. 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 120	1 in 2,000
South Asian	~43k	1 in 100	1 in 1,500
Remaining (unassigned)	~30k	1 in 65	1 in 2,000
European (Finnish)	~27k	1 in 190	1 in 1,100
Admixed American	~22k	1 in 88	1 in 920
African / African American	~21k	1 in 150	1 in 780
East Asian	~20k	1 in 110	≈ 1 in 5,000
Ashkenazi Jewish	~13k	1 in 760	≈ 1 in 13,000
Middle Eastern	~2,884	1 in 90	≈ 1 in 1,400

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 6 coding exons well covered in gnomAD exomes and genomes.? see exons ↓