FAM163B

Chr 9

family with sequence similarity 163 member B

Also known as: C9orf166

FAM163B encodes a protein predicted to be located in membrane. Mutations cause autosomal recessive developmental and epileptic encephalopathy with onset in infancy, characterized by severe intellectual disability, epilepsy, and brain malformations. The gene shows tolerance to loss-of-function variants (pLI 0.03, LOEUF 1.87), suggesting the recessive inheritance pattern fits with the constraint data.

ResearchSummary from RefSeq
MultiplemechanismLOEUF 1.87
Clinical SummaryFAM163B
Population Constraint (gnomAD)
Low constraint (pLI 0.03) — 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
1.87LOEUF
pLI 0.026
Z-score 0.04
OE 0.97 (0.361.87)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.76Z-score
OE missense 1.26 (1.061.51)
84 obs / 66.6 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.97 (0.361.87)
00.351.4
Missense OE1.26 (1.061.51)
00.61.4
Synonymous OE1.19
01.21.6
LoF obs/exp: 2 / 2.1Missense obs/exp: 84 / 66.6Syn Z: -0.85
DN
0.7325th %ile
GOF
0.74top 25%
LOF
0.3842th %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

FAM163B · 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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