2-165941130-G-A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1PM2

The NM_024753.5(TTC21B):​c.607C>T​(p.Gln203*) variant causes a stop gained change. The variant allele was found at a frequency of 0.000000684 in 1,461,654 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TTC21B
NM_024753.5 stop_gained

Scores

4
2
1

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 4.83
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-AS1 (HGNC:41115): (TTC21B antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 10 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TTC21BNM_024753.5 linkc.607C>T p.Gln203* stop_gained 6/29 ENST00000243344.8 NP_079029.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TTC21BENST00000243344.8 linkc.607C>T p.Gln203* stop_gained 6/291 NM_024753.5 ENSP00000243344.7 Q7Z4L5-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461654
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727124
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
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:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Asphyxiating thoracic dystrophy 4;C3151186:Nephronophthisis 12 Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsMar 27, 2024- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.60
CADD
Pathogenic
37
DANN
Uncertain
1.0
Eigen
Pathogenic
0.84
Eigen_PC
Pathogenic
0.67
FATHMM_MKL
Uncertain
0.97
D
Vest4
0.37
GERP RS
3.5
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

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-166797640; API