rs146496725

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_024753.5(TTC21B):​c.3004C>G​(p.Leu1002Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00805 in 1,612,974 control chromosomes in the GnomAD database, including 74 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. L1002L) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0051 ( 4 hom., cov: 32)
Exomes 𝑓: 0.0084 ( 70 hom. )

Consequence

TTC21B
NM_024753.5 missense

Scores

12
6

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:12

Conservation

PhyloP100: 3.29

Publications

15 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):
  • asphyxiating thoracic dystrophy 4
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • nephronophthisis 12
    Inheritance: AR, AD Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
  • 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: Benign. The variant received -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.009657979).
BP6
Variant 2-165890935-G-C is Benign according to our data. Variant chr2-165890935-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 195777.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.00513 (780/152112) while in subpopulation NFE AF = 0.00896 (609/67974). AF 95% confidence interval is 0.00837. There are 4 homozygotes in GnomAd4. There are 333 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 4 AR,AD gene

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024753.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTC21B
NM_024753.5
MANE Select
c.3004C>Gp.Leu1002Val
missense
Exon 23 of 29NP_079029.3

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTC21B
ENST00000243344.8
TSL:1 MANE Select
c.3004C>Gp.Leu1002Val
missense
Exon 23 of 29ENSP00000243344.7Q7Z4L5-1
TTC21B
ENST00000679840.1
c.3004C>Gp.Leu1002Val
missense
Exon 23 of 27ENSP00000505248.1A0A7P0T8P4
TTC21B
ENST00000679799.1
c.3004C>Gp.Leu1002Val
missense
Exon 23 of 28ENSP00000505208.1A0A494C0N4

Frequencies

GnomAD3 genomes
AF:
0.00513
AC:
780
AN:
151994
Hom.:
4
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00205
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00282
Gnomad ASJ
AF:
0.00231
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00207
Gnomad FIN
AF:
0.00151
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00896
Gnomad OTH
AF:
0.00430
GnomAD2 exomes
AF:
0.00529
AC:
1324
AN:
250162
AF XY:
0.00533
show subpopulations
Gnomad AFR exome
AF:
0.00138
Gnomad AMR exome
AF:
0.00327
Gnomad ASJ exome
AF:
0.00378
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00185
Gnomad NFE exome
AF:
0.00889
Gnomad OTH exome
AF:
0.00427
GnomAD4 exome
AF:
0.00836
AC:
12211
AN:
1460862
Hom.:
70
Cov.:
31
AF XY:
0.00818
AC XY:
5946
AN XY:
726738
show subpopulations
African (AFR)
AF:
0.00105
AC:
35
AN:
33448
American (AMR)
AF:
0.00329
AC:
147
AN:
44690
Ashkenazi Jewish (ASJ)
AF:
0.00391
AC:
102
AN:
26118
East Asian (EAS)
AF:
0.0000505
AC:
2
AN:
39602
South Asian (SAS)
AF:
0.00253
AC:
218
AN:
86236
European-Finnish (FIN)
AF:
0.00212
AC:
113
AN:
53388
Middle Eastern (MID)
AF:
0.00278
AC:
16
AN:
5764
European-Non Finnish (NFE)
AF:
0.00999
AC:
11106
AN:
1111256
Other (OTH)
AF:
0.00782
AC:
472
AN:
60360
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.444
Heterozygous variant carriers
0
595
1190
1786
2381
2976
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
438
876
1314
1752
2190
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00513
AC:
780
AN:
152112
Hom.:
4
Cov.:
32
AF XY:
0.00448
AC XY:
333
AN XY:
74382
show subpopulations
African (AFR)
AF:
0.00205
AC:
85
AN:
41514
American (AMR)
AF:
0.00282
AC:
43
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00231
AC:
8
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5160
South Asian (SAS)
AF:
0.00207
AC:
10
AN:
4822
European-Finnish (FIN)
AF:
0.00151
AC:
16
AN:
10588
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00896
AC:
609
AN:
67974
Other (OTH)
AF:
0.00426
AC:
9
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.504
Heterozygous variant carriers
0
42
83
125
166
208
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00827
Hom.:
5
Bravo
AF:
0.00529
TwinsUK
AF:
0.00836
AC:
31
ALSPAC
AF:
0.0112
AC:
43
ESP6500AA
AF:
0.00159
AC:
7
ESP6500EA
AF:
0.00907
AC:
78
ExAC
AF:
0.00557
AC:
676
Asia WGS
AF:
0.000867
AC:
3
AN:
3476
EpiCase
AF:
0.00965
EpiControl
AF:
0.00753

ClinVar

ClinVar submissions
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
4
not provided (4)
-
1
2
not specified (3)
-
-
1
Asphyxiating thoracic dystrophy 4 (1)
-
-
1
Chronic kidney disease (1)
-
-
1
Connective tissue disorder (1)
-
-
1
Jeune thoracic dystrophy;C0687120:Nephronophthisis (1)
-
-
1
Joubert syndrome 1 (1)
-
-
1
Nephronophthisis 12 (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.16
BayesDel_addAF
Benign
-0.18
T
BayesDel_noAF
Uncertain
-0.020
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.42
T
Eigen
Uncertain
0.50
Eigen_PC
Uncertain
0.50
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Uncertain
0.96
D
M_CAP
Benign
0.027
D
MetaRNN
Benign
0.0097
T
MetaSVM
Benign
-0.75
T
MutationAssessor
Uncertain
2.7
M
PhyloP100
3.3
PrimateAI
Uncertain
0.53
T
PROVEAN
Uncertain
-2.6
D
REVEL
Benign
0.24
Sift
Uncertain
0.0030
D
Sift4G
Uncertain
0.026
D
Polyphen
0.96
D
Vest4
0.66
MVP
0.45
MPC
0.14
ClinPred
0.030
T
GERP RS
4.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.52
gMVP
0.39
Mutation Taster
=83/17
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: rs146496725; hg19: chr2-166747445; COSMIC: COSV99074759; COSMIC: COSV99074759; API