Genetic Variant ARPC4-TTLL3:c.331-2818C>T (chr3-9810125-C-T) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_001025930.5(TTLL3):c.119C>T(p.Pro40Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000395 in 1,469,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/18 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: 𝑓 0.00022 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

TTLL3
NM_001025930.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -1.69

Variant links:

Genes affected

ARPC4-TTLL3 (HGNC:38830): (ARPC4-TTLL3 readthrough) This locus represents naturally occurring read-through transcription between the neighboring ARPC4 (actin related protein 2/3 complex, subunit 4) and TTLL3 (tubulin tyrosine ligase-like family, member 3) genes. The read-through transcript encodes a fusion protein that shares sequence identity with each individual gene product. [provided by RefSeq, Nov 2010]

ARPC4-TTLL3 links:

TTLL3 (HGNC:24483): (tubulin tyrosine ligase like 3) Enables protein-glycine ligase activity. Predicted to be involved in axoneme assembly and flagellated sperm motility. Predicted to be located in axoneme; microtubule cytoskeleton; and sperm flagellum. [provided by Alliance of Genome Resources, Apr 2022]

TTLL3 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.013896108).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TTLL3	NM_001387446.1 link	c.-311C>T		upstream_gene_variant		ENST00000685419.1	NP_001374375.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ARPC4-TTLL3	ENST00000397256.5 link	c.331-2818C>T		intron_variant	Intron 4 of 11	5		ENSP00000380427.1		A0A0A6YYG9
TTLL3	ENST00000685419.1 link	c.-311C>T		upstream_gene_variant			NM_001387446.1	ENSP00000510679.1		A0A8I5KXU2

Frequencies

GnomAD3 genomes

AF:

0.000217

AC:

AN:

152060

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000796

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000276

AC:

AN:

72520

Hom.:

AF XY:

0.00

AC XY:

AN XY:

42032

show subpopulations

Gnomad AFR exome

AF:

0.00238

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000190

AC:

AN:

1317756

Hom.:

Cov.:

AF XY:

0.0000170

AC XY:

AN XY:

648926

show subpopulations

Gnomad4 AFR exome

AF:

0.000716

Gnomad4 AMR exome

AF:

0.0000805

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000190

Gnomad4 OTH exome

AF:

0.0000365

GnomAD4 genome

AF:

0.000217

AC:

AN:

152060

Hom.:

Cov.:

AF XY:

0.000202

AC XY:

AN XY:

74268

show subpopulations

Gnomad4 AFR

AF:

0.000796

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.000185

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Jan 09, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.119C>T (p.P40L) alteration is located in exon 1 (coding exon 1) of the TTLL3 gene. This alteration results from a C to T substitution at nucleotide position 119, causing the proline (P) at amino acid position 40 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Benign

-0.61

BayesDel_noAF

Benign

-0.65

CADD

Benign

2.9

DANN

Benign

0.97

Eigen

Benign

-0.92

Eigen_PC

Benign

-1.0

FATHMM_MKL

Benign

0.034

LIST_S2

Benign

0.45

M_CAP

Benign

0.017

MetaRNN

Benign

0.014

MetaSVM

Benign

-0.92

PrimateAI

Benign

0.48

PROVEAN

Benign

-1.5

REVEL

Benign

0.025

Sift

Benign

0.51

Sift4G

Benign

0.76

Vest4

0.063

MutPred

0.18

Loss of relative solvent accessibility (P = 0.0186);

MVP

0.23

MPC

0.091

ClinPred

0.029

GERP RS

0.36

gMVP

0.090

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over