rs34925776

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_024753.5(TTC21B):​c.3223G>T​(p.Val1075Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,352 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V1075L) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TTC21B
NM_024753.5 missense

Scores

6
13

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: -0.449

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • nephronophthisis 12
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae)
  • asphyxiating thoracic dystrophy 4
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • Jeune syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • nephronophthisis 2
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.18655333).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTC21BNM_024753.5 linkc.3223G>T p.Val1075Phe missense_variant Exon 24 of 29 ENST00000243344.8 NP_079029.3
TTC21BXM_017004967.2 linkc.3223G>T p.Val1075Phe missense_variant Exon 24 of 28 XP_016860456.1
TTC21BXM_047445870.1 linkc.2569G>T p.Val857Phe missense_variant Exon 20 of 25 XP_047301826.1
TTC21BXM_011511871.4 linkc.2473G>T p.Val825Phe missense_variant Exon 19 of 24 XP_011510173.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTC21BENST00000243344.8 linkc.3223G>T p.Val1075Phe missense_variant Exon 24 of 29 1 NM_024753.5 ENSP00000243344.7

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461352
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
726972
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33450
American (AMR)
AF:
0.00
AC:
0
AN:
44704
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26122
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39626
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86236
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53392
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1111694
Other (OTH)
AF:
0.00
AC:
0
AN:
60364
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Benign
-0.066
T
BayesDel_noAF
Benign
-0.33
CADD
Benign
8.0
DANN
Uncertain
0.99
DEOGEN2
Benign
0.37
T
Eigen
Benign
-0.83
Eigen_PC
Benign
-0.92
FATHMM_MKL
Benign
0.12
N
LIST_S2
Uncertain
0.94
D
M_CAP
Benign
0.050
D
MetaRNN
Benign
0.19
T
MetaSVM
Benign
-0.90
T
MutationAssessor
Uncertain
2.2
M
PhyloP100
-0.45
PrimateAI
Benign
0.29
T
PROVEAN
Uncertain
-3.0
D
REVEL
Benign
0.15
Sift
Uncertain
0.0080
D
Sift4G
Uncertain
0.036
D
Polyphen
0.55
P
Vest4
0.46
MutPred
0.33
Gain of helix (P = 0.1736);
MVP
0.18
MPC
0.054
ClinPred
0.83
D
GERP RS
-5.7
Varity_R
0.29
gMVP
0.48
Mutation Taster
=75/25
polymorphism

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

Other links and lift over

dbSNP: rs34925776; hg19: chr2-166747029; COSMIC: COSV54636406; API