rs77106136

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_024753.5(TTC21B):​c.1870A>G​(p.Ile624Val) variant causes a missense change. The variant allele was found at a frequency of 0.00113 in 1,614,190 control chromosomes in the GnomAD database, including 21 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.0056 ( 9 hom., cov: 32)
Exomes 𝑓: 0.00066 ( 12 hom. )

Consequence

TTC21B
NM_024753.5 missense

Scores

1
16

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:8

Conservation

PhyloP100: 4.88

Publications

5 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: Benign. The variant received -20 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0028590262).
BP6
Variant 2-165917286-T-C is Benign according to our data. Variant chr2-165917286-T-C is described in ClinVar as Benign. ClinVar VariationId is 331831.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.0056 (853/152332) while in subpopulation AFR AF = 0.0197 (818/41574). AF 95% confidence interval is 0.0186. There are 9 homozygotes in GnomAd4. There are 414 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 9 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

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTC21B
NM_024753.5
MANE Select
c.1870A>Gp.Ile624Val
missense
Exon 14 of 29NP_079029.3

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TTC21B
ENST00000243344.8
TSL:1 MANE Select
c.1870A>Gp.Ile624Val
missense
Exon 14 of 29ENSP00000243344.7
TTC21B
ENST00000679840.1
c.1870A>Gp.Ile624Val
missense
Exon 14 of 27ENSP00000505248.1
TTC21B
ENST00000679799.1
c.1870A>Gp.Ile624Val
missense
Exon 14 of 28ENSP00000505208.1

Frequencies

GnomAD3 genomes
AF:
0.00561
AC:
854
AN:
152214
Hom.:
9
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0198
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00137
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000735
Gnomad OTH
AF:
0.00382
GnomAD2 exomes
AF:
0.00157
AC:
395
AN:
251386
AF XY:
0.00126
show subpopulations
Gnomad AFR exome
AF:
0.0204
Gnomad AMR exome
AF:
0.00147
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.000978
GnomAD4 exome
AF:
0.000665
AC:
972
AN:
1461858
Hom.:
12
Cov.:
31
AF XY:
0.000575
AC XY:
418
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.0230
AC:
771
AN:
33480
American (AMR)
AF:
0.00152
AC:
68
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000765
AC:
2
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39682
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00191
AC:
11
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000432
AC:
48
AN:
1112002
Other (OTH)
AF:
0.00116
AC:
70
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
Heterozygous variant carriers
0
57
114
170
227
284
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
28
56
84
112
140
<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:
0.00560
AC:
853
AN:
152332
Hom.:
9
Cov.:
32
AF XY:
0.00556
AC XY:
414
AN XY:
74494
show subpopulations
African (AFR)
AF:
0.0197
AC:
818
AN:
41574
American (AMR)
AF:
0.00137
AC:
21
AN:
15298
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68024
Other (OTH)
AF:
0.00378
AC:
8
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
40
80
120
160
200
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:
0.00252
Hom.:
14
Bravo
AF:
0.00651
ESP6500AA
AF:
0.0227
AC:
100
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.00180
AC:
219
Asia WGS
AF:
0.000577
AC:
2
AN:
3478
EpiCase
AF:
0.000273
EpiControl
AF:
0.000119

ClinVar

ClinVar submissions as Germline
Significance:Benign
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
4
not provided (4)
-
-
1
Asphyxiating thoracic dystrophy 4 (1)
-
-
1
Jeune thoracic dystrophy;C0687120:Nephronophthisis (1)
-
-
1
Nephronophthisis 12 (1)
-
-
1
not specified (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.061
BayesDel_addAF
Benign
-0.55
T
BayesDel_noAF
Benign
-0.55
CADD
Benign
12
DANN
Benign
0.29
DEOGEN2
Benign
0.058
T
Eigen
Benign
-0.84
Eigen_PC
Benign
-0.57
FATHMM_MKL
Benign
0.29
N
LIST_S2
Benign
0.74
T
MetaRNN
Benign
0.0029
T
MetaSVM
Benign
-0.93
T
MutationAssessor
Benign
-1.8
N
PhyloP100
4.9
PrimateAI
Benign
0.26
T
PROVEAN
Benign
0.79
N
REVEL
Uncertain
0.29
Sift
Benign
1.0
T
Sift4G
Benign
1.0
T
Polyphen
0.0
B
Vest4
0.076
MVP
0.32
MPC
0.027
ClinPred
0.0045
T
GERP RS
4.9
Varity_R
0.037
gMVP
0.16
Mutation Taster
=93/7
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs77106136; hg19: chr2-166773796; API