rs200255917

Variant summary

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

The NM_024753.5(TTC21B):​c.783G>T​(p.Gly261=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000819 in 1,612,612 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 0.000085 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000081 ( 0 hom. )

Consequence

TTC21B
NM_024753.5 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:3

Conservation

PhyloP100: 0.210
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]

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=-0.21).
BP6
Variant 2-165932985-C-A is Benign according to our data. Variant chr2-165932985-C-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 528909.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Benign=1, Uncertain_significance=2}.
BP7
Synonymous conserved (PhyloP=0.21 with no splicing effect.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTC21BNM_024753.5 linkuse as main transcriptc.783G>T p.Gly261= synonymous_variant 7/29 ENST00000243344.8 NP_079029.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTC21BENST00000243344.8 linkuse as main transcriptc.783G>T p.Gly261= synonymous_variant 7/291 NM_024753.5 ENSP00000243344 P1Q7Z4L5-1

Frequencies

GnomAD3 genomes
AF:
0.0000855
AC:
13
AN:
152056
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00260
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000147
AC:
37
AN:
251086
Hom.:
0
AF XY:
0.000103
AC XY:
14
AN XY:
135704
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000868
Gnomad ASJ exome
AF:
0.00258
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000529
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.0000815
AC:
119
AN:
1460556
Hom.:
0
Cov.:
30
AF XY:
0.0000785
AC XY:
57
AN XY:
726560
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.000134
Gnomad4 ASJ exome
AF:
0.00299
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000135
Gnomad4 OTH exome
AF:
0.000315
GnomAD4 genome
AF:
0.0000855
AC:
13
AN:
152056
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74286
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.000131
Gnomad4 ASJ
AF:
0.00260
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000405
Hom.:
0
Bravo
AF:
0.0000945

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Asphyxiating thoracic dystrophy 4 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Nephronophthisis 12 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Jeune thoracic dystrophy;C0687120:Nephronophthisis Benign:1
Benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 02, 2024- -
not provided Benign:1
Likely benign, criteria provided, single submitterclinical testingGeneDxDec 14, 2020- -
TTC21B-related disorder Benign:1
Likely benign, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesJan 13, 2020This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.21
CADD
Benign
6.3
DANN
Benign
0.72
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7

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.

Other links and lift over

dbSNP: rs200255917; hg19: chr2-166789495; API