FRMPD1

Chr 9

FERM and PDZ domain containing 1

Also known as: FRMD2

FRMPD1 encodes a protein that stabilizes membrane-bound GPSM1 and promotes its interaction with GNAI1, functioning in G protein-coupled receptor signaling and protein localization to membranes. Mutations cause bifrontoparietal polymicrogyria, a brain malformation disorder with autosomal recessive inheritance. This gene shows tolerance to loss-of-function variants (pLI near zero), consistent with the recessive inheritance pattern observed clinically.

OMIMResearchSummary from RefSeq, UniProt
MultiplemechanismLOEUF 0.66
Clinical SummaryFRMPD1
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
0.66LOEUF
pLI 0.000
Z-score 3.77
OE 0.48 (0.360.66)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
0.67Z-score
OE missense 0.94 (0.880.99)
834 obs / 890.1 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.48 (0.360.66)
00.351.4
Missense OE0.94 (0.880.99)
00.61.4
Synonymous OE1.01
01.21.6
LoF obs/exp: 30 / 62.0Missense obs/exp: 834 / 890.1Syn Z: -0.08
DN
0.6357th %ile
GOF
0.6540th %ile
LOF
0.3744th %ile

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

GOFprediction above median
DNprediction 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

FRMPD1 · protein map & ClinVar variants

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

3D Protein StructureAlphaFold

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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