CFAP157

Chr 9

cilia and flagella associated protein 157

Also known as: C9orf117

NCBI Gene: 286207 ENSG00000160401 UniProt: Q5JU67 OMIM: 621392

The protein is specifically required during spermatogenesis for flagellum morphogenesis and sperm motility, with predicted microtubule binding activity and involvement in sperm axoneme assembly. Mutations cause primary ciliary dyskinesia with or without situs inversus, inherited in an autosomal recessive pattern. The gene shows very low constraint against loss-of-function variants, consistent with a recessive disorder affecting primarily reproductive function.

OMIM ResearchSummary from RefSeq, UniProt

Predicted to enable microtubule binding activity. Predicted to be involved in sperm axoneme assembly. Predicted to be located in cilium. Predicted to be active in ciliary basal body. [provided by Alliance of Genome Resources, Jun 2026]

OMIM ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

1.16

LOEUF

Multiple*

Mechanism· predicted

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Tolerant — LoF & missense variants common in population

LoF Constraint?

1.16LOEUF

pLI 0.000

Z-score 0.95

OE 0.80 (0.56–1.16)

Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?

0.75Z-score

OE missense 0.88 (0.80–0.97)

271 obs / 308.1 exp

Tolerant

Mild missense constraint

Observed / Expected Ratios?

LoF OE?0.80 (0.56–1.16)

0≤0.351.4

Missense OE?0.88 (0.80–0.97)

0≤0.61.4

Synonymous OE?0.85

0≤1.21.6

LoF obs/exp: 20 / 25.2Missense obs/exp: 271 / 308.1Syn Z: 1.35

Background carrier burden — how many people carry a rare variant somewhere in CFAP157?

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 69

719 rare PASS variants

Rare truncating (LoF)

1 in 500

129 rare PASS variants

Rare synonymous (reference)

1 in 160

297 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for CFAP157. 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 76	1 in 880
South Asian	~43k	1 in 54	1 in 580
Remaining (unassigned)	~30k	1 in 60	1 in 770
European (Finnish)	~27k	1 in 130	1 in 1,300
Admixed American	~22k	1 in 62	1 in 850
African / African American	~21k	1 in 91	1 in 1,500
East Asian	~20k	1 in 68	1 in 840
Ashkenazi Jewish	~13k	1 in 220	1 in 2,600
Middle Eastern	~2,884	1 in 54	1 in 350

Each group is summed over the variants that are rare in that group. Differences mostly reflect how many people were sampled and how much variation each ancestry carries, not disease risk.

Exome coverage (gnomAD): All 9 coding exons well covered in gnomAD exomes and genomes.? see exons ↓