TMEM255B

protein-coding

transmembrane protein 255B

Gene summary

Predicted to be located in membrane. [provided by Alliance of Genome Resources, Jul 2025]

Previous symbols:

FAM70B

MANE transcript

NM_182614.4

Inheritance

—

ClinVar variants

U:62B:9

Top phenotype

—

gnomAD constraint

pLI —, LoF o/e 1.13

Max pathogenic AF

—

Genomic locus

chr13:113,759,226-113,816,995

External References & Databases

Ensembl (ENSG00000184497)

Transcript & Mutation Effects

hg38 • Region Span ~57.8 kb

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GenCC Phenotypes & Disease Associations

Curated gene-disease validity assertions and inheritance patterns

No GenCC data available for this gene.

ClinVar Associated Diseases & Phenotypes

Reported disease conditions connected to TMEM255B variants in ClinVar

2 Conditions Cataloged

not specifiedTotal: 62

not providedTotal: 2

ClinVar Variants & Pathogenicity by Type

Statistics based on transcript NM_182614.4. Only rare variants are included.

We include only reliable ClinVar variants with their consequences to MANE Select, MANE Plus Clinical transcripts, or transcripts with TSL equal to 1. Click a count to filter the variants table below.

Slight differences between displayed counts and ClinVar may occur due to a different transcript/consequence chosen by our variant effect predictor, or because we classify Benign/Likely benign as Likely benign and Pathogenic/Likely pathogenic as Likely pathogenic.

Effect	PathogenicP	Likely pathogenicLP	VUS	Likely benignLB	BenignB	Sum
synonymous			1 clinvar	2 clinvar		3
missense			59 clinvar	7 clinvar		66
nonsense						0
start loss						0
frameshift						0
splice donor/acceptor (+/-2bp)			2 clinvar			2
Total	0	0	62	9	0	71

Loading ClinVar variants...

Transcript Catalog

Annotated transcript isoforms across RefSeq and Ensembl databases

Showing 4 of 67 transcripts

Transcript ID	Source	Protein ID	Coding Exons	MANE Status
NM_182614.4	RefSeq	NP_872420.1	9	MANE Select
ENST00000375353.5	Ensembl	ENSP00000364502.3	9	MANE Select
NM_001348663.2	RefSeq	NP_001335592.1	8	Standard
ENST00000488362.5	Ensembl	ENSP00000479391.1	5	Standard

Gene Ontology (GO) Annotations & Pathways

Biological processes, molecular functions, cellular components and pathways

Cellular Component

integral component of membrane

gnomAD Constraint

Source: gnomAD

Gene type: protein_coding
Transcript type: protein_coding
Transcript: ENST00000375353
Coding exons: 9
Length: 52711
Individuals with no LoFs: 103325
Homozygous LoFs: 1765
Heterozygous LoFs: 20657
Defined: 125747
p: 0.0935

	Z-Score	Observed	Expected	Observed/Expected	Mutation Rate	Total Possible
Missense	-0.179	206	199	1.04	0.0000126	2037
Missense (PolyPhen)		77	73.979	1.0408		803
Synonymous	-0.401	106	101	1.05	0.00000791	718
Loss of Function	-0.454	16	14.2	1.13	6.00e-7	173

Population LoF Frequency

Population	CAF	p-value	Status
African	0.22	0.17	notable
Latino/Admixed American	0.075	0.072	notable
Ashkenazi Jewish	0.22	0.20	notable
East Asian	0.00093	0.00092	rare
Finnish	0.098	0.092	notable
European (Non-Finnish)	0.12	0.11	notable
South Asian	0.041	0.036	notable
Other	0.13	0.12	notable

dbNSFP Gene Annotations

Source: dbNSFP

Intolerance Scores

RVIS EVS: 0.65
RVIS percentile EVS: 84.12

Essentials

Essential (CRISPR): N
Essential (CRISPR2): N
Essential (gene trap): N

Gene Damage Prediction

	All	Recessive	Dominant
Mendelian	Medium	Medium	Medium
Primary Immunodeficiency	Medium	Medium	Medium
Cancer	Medium	Medium	Medium