TTPAL

protein-coding

alpha tocopherol transfer protein like

Gene summary

Predicted to enable phosphatidylinositol bisphosphate binding activity. Located in membrane. [provided by Alliance of Genome Resources, Jul 2025]

Previous symbols:

C20orf121

MANE transcript

NM_001039199.3

Inheritance

—

ClinVar variants

U:42B:1

Top phenotype

—

gnomAD constraint

pLI —, LoF o/e 0.29

Max pathogenic AF

—

Genomic locus

chr20:44,475,874-44,494,603

External References & Databases

Ensembl (ENSG00000124120)

Transcript & Mutation Effects

hg38 • Region Span ~18.7 kb

Loading mutation effect viewer...

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 TTPAL variants in ClinVar

1 Conditions Cataloged

not specifiedTotal: 40

ClinVar Variants & Pathogenicity by Type

Statistics based on transcript NM_001039199.3. 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						0
missense			39 clinvar	1 clinvar		40
nonsense						0
start loss						0
frameshift						0
splice donor/acceptor (+/-2bp)			3 clinvar			3
Total	0	0	42	1	0	43

Loading ClinVar variants...

Transcript Catalog

Annotated transcript isoforms across RefSeq and Ensembl databases

Showing 4 of 84 transcripts

Transcript ID	Source	Protein ID	Coding Exons	MANE Status
NM_001039199.3	RefSeq	NP_001034288.1	4	MANE Select
ENST00000262605.9	Ensembl	ENSP00000262605.4	4	MANE Select
NM_001261839.2	RefSeq	NP_001248768.1	4	Standard
NM_024331.5	RefSeq	NP_077307.2	4	Standard

Gene Ontology (GO) Annotations & Pathways

Biological processes, molecular functions, cellular components and pathways

Cellular Component

membrane

gnomAD Constraint

Source: gnomAD

Gene type: protein_coding
Transcript type: protein_coding
Transcript: ENST00000372904
Coding exons: 4
Length: 18719
Individuals with no LoFs: 125732
Homozygous LoFs: 0
Heterozygous LoFs: 16
Defined: 125748
p: 0.0000636

	Z-Score	Observed	Expected	Observed/Expected	Mutation Rate	Total Possible
Missense	1.42	144	201	0.717	0.0000117	2208
Missense (PolyPhen)		51	81.78	0.62362		905
Synonymous	0.146	82	83.7	0.980	0.00000499	715
Loss of Function	2.44	4	13.8	0.290	8.86e-7	147

Population LoF Frequency

Population	CAF	p-value	Status
African	0.000062	0.000062	rare
Latino/Admixed American	0.000029	0.000029	rare
Ashkenazi Jewish	0	0.0	absent
East Asian	0.00016	0.00016	rare
Finnish	0	0.0	absent
European (Non-Finnish)	0.000070	0.000070	rare
South Asian	0.000099	0.000098	rare
Other	0	0.0	absent

dbNSFP Gene Annotations

Source: dbNSFP

Function: FUNCTION: May act as a protein that binds a hydrophobic ligand. {ECO:0000305}.;

Recessive Scores

pRec: 0.106

Intolerance Scores

LoFtool: 0.243
RVIS EVS: 0.28
RVIS percentile EVS: 71.27

Essentials

Essential (CRISPR): N
Essential (CRISPR2): N
Essential (gene trap): N
Indispensability pred.: E
Indispensability score: 0.554

Gene Damage Prediction

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