SEPTIN2

Chr 2

septin 2

Also known as: DIFF6, NEDD-5, NEDD5, Pnutl3, SEPT2, Septin-2, hNedd5

SEPTIN2 encodes a filament-forming cytoskeletal GTPase that is essential for actin cytoskeleton organization, mitotic spindle function, ciliogenesis, and sperm tail structural integrity. Mutations cause autosomal recessive primary ciliary dyskinesia with reduced generation of multiple motile cilia, presenting with respiratory symptoms, situs abnormalities, and male infertility. The gene shows significant constraint against loss-of-function variants (LOEUF 0.496), indicating that complete loss of function is likely deleterious.

Summary from RefSeq, UniProt
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0
Active trials
4
Pubs (1 yr)
0
P/LP submissions
P/LP missense
0.50
LOEUF
Multiple*
Mechanism· predicted
Clinical SummarySEPTIN2
Population Constraint (gnomAD)
Constrained for loss-of-function variants (OE-LoF 0.24) despite low pLI — interpret in context.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Moderate LoF intolerance
LoF Constraint
0.50LOEUF
pLI 0.288
Z-score 3.26
OE 0.24 (0.120.50)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint
1.99Z-score
OE missense 0.61 (0.530.71)
125 obs / 205.2 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.24 (0.120.50)
00.351.4
Missense OE0.61 (0.530.71)
00.61.4
Synonymous OE1.15
01.21.6
LoF obs/exp: 5 / 21.2Missense obs/exp: 125 / 205.2Syn Z: -1.02
DN
0.75top 25%
GOF
0.73top 25%
LOF
0.3357th %ile

This gene has evidence for multiple mechanisms of pathogenicity (dominant-negative and gain-of-function). Both the Badonyi & Marsh prediction and the broader genomic evidence point to dominant-negative as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

DNprediction above median
GOFprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

SEPTIN2 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

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Clinical Literature
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