dbSNP rs141664029: TTC21B:p.Gly183Gly (chr2-165943222-A-G) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_ModerateBP6BP7

The NM_024753.5(TTC21B):c.549T>C(p.Gly183Gly) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000353 in 1,613,464 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00013 ( 1 hom., cov: 33)

Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

TTC21B
NM_024753.5 synonymous

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:3

Conservation

PhyloP100: 2.61

Variant links:

Genes affected

TTC21B (HGNC:25660): (tetratricopeptide repeat domain 21B) This gene encodes a member of TTC21 family, containing several tetratricopeptide repeat (TPR) domains. This protein is localized to the cilium axoneme, and may play a role in retrograde intraflagellar transport in cilia. Mutations in this gene are associated with various ciliopathies, nephronophthisis 12, and asphyxiating thoracic dystrophy 4. [provided by RefSeq, Oct 2011]

TTC21B links:

TTC21B-AS1 (HGNC:41115): (TTC21B antisense RNA 1)

TTC21B-AS1 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 (BayesDel_noAF=-0.4).

BP6

Variant 2-165943222-A-G is Benign according to our data. Variant chr2-165943222-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 261784.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Uncertain_significance=1}.

BP7

Synonymous conserved (PhyloP=2.61 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TTC21B	NM_024753.5 link	c.549T>C	p.Gly183Gly	synonymous_variant	Exon 5 of 29	ENST00000243344.8	NP_079029.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TTC21B	ENST00000243344.8 link	c.549T>C	p.Gly183Gly	synonymous_variant	Exon 5 of 29	1	NM_024753.5	ENSP00000243344.7		Q7Z4L5-1

Frequencies

GnomAD3 genomes

AF:

0.000131

AC:

AN:

152138

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000338

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000327

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:

0.000478

GnomAD3 exomes

AF:

0.000111

AC:

AN:

251354

Hom.:

AF XY:

0.0000736

AC XY:

AN XY:

135844

show subpopulations

Gnomad AFR exome

AF:

0.000431

Gnomad AMR exome

AF:

0.000434

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:

0.00000880

Gnomad OTH exome

AF:

0.000815

GnomAD4 exome

AF:

0.0000253

AC:

AN:

1461326

Hom.:

Cov.:

AF XY:

0.0000220

AC XY:

AN XY:

726986

show subpopulations

Gnomad4 AFR exome

AF:

0.000179

Gnomad4 AMR exome

AF:

0.000447

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:

0.00000360

Gnomad4 OTH exome

AF:

0.000116

GnomAD4 genome

AF:

0.000131

AC:

AN:

152138

Hom.:

Cov.:

AF XY:

0.000135

AC XY:

AN XY:

74330

show subpopulations

Gnomad4 AFR

AF:

0.000338

Gnomad4 AMR

AF:

0.000327

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:

0.000478

Alfa

AF:

0.000427

Hom.:

Bravo

AF:

0.000162

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:1Benign:1

Mar 16, 2016

Eurofins Ntd Llc (ga)

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 23, 2019

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified

Benign:1

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jeune thoracic dystrophy;C0687120:Nephronophthisis

Benign:1

Jan 18, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.40

CADD

Benign

9.2

DANN

Benign

0.90

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

2.8

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