Genetic Variant TTC21B:c.1386+15G>A (chr2-165929120-C-T) – ACMG Classification: Benign (-12 pts)

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_StrongBP6_Very_Strong

The NM_024753.5(TTC21B):c.1386+15G>A variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000218 in 1,607,384 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 Likely benign (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000022 ( 0 hom. )

Consequence

TTC21B
NM_024753.5 intron

Scores

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: -1.23

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):

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

TTC21B links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -12 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.78).

BP6

Variant 2-165929120-C-T is Benign according to our data. Variant chr2-165929120-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 261766.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTC21B	NM_024753.5	MANE Select	c.1386+15G>A		intron	N/A	NP_079029.3

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	Effect	Exon Rank	Protein	UniProt
TTC21B	ENST00000243344.8	TSL:1 MANE Select	c.1386+15G>A	intron	N/A	ENSP00000243344.7	Q7Z4L5-1
TTC21B	ENST00000464374.5	TSL:1	n.1441G>A	non_coding_transcript_exon	Exon 11 of 11
TTC21B	ENST00000679840.1		c.1386+15G>A	intron	N/A	ENSP00000505248.1	A0A7P0T8P4

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152034

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.000288

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

GnomAD2 exomes

AF:

0.0000320

AC:

AN:

250054

AF XY:

0.0000296

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.0000994

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000531

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000220

AC:

AN:

1455232

Hom.:

Cov.:

AF XY:

0.0000221

AC XY:

AN XY:

724342

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33302

American (AMR)

AF:

0.0000224

AC:

AN:

44602

Ashkenazi Jewish (ASJ)

AF:

0.000192

AC:

AN:

26044

East Asian (EAS)

AF:

0.00

AC:

AN:

39506

South Asian (SAS)

AF:

0.0000349

AC:

AN:

85912

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53352

Middle Eastern (MID)

AF:

0.000697

AC:

AN:

5740

European-Non Finnish (NFE)

AF:

0.0000117

AC:

AN:

1106598

Other (OTH)

AF:

0.0000997

AC:

AN:

60176

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.458

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000197

AC:

AN:

152152

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74398

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41558

American (AMR)

AF:

0.00

AC:

AN:

15264

Ashkenazi Jewish (ASJ)

AF:

0.000288

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5186

South Asian (SAS)

AF:

0.00

AC:

AN:

4824

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10614

Middle Eastern (MID)

AF:

0.00

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.0000294

AC:

AN:

67918

Other (OTH)

AF:

0.00

AC:

AN:

2112

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.475

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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:

0.00

Hom.:

Bravo

AF:

0.0000113

ClinVar

ClinVar submissions

Significance:Likely benign

Revision:criteria provided, multiple submitters, no conflicts

View on ClinVar

Pathogenic

VUS

Benign

Condition

Asphyxiating thoracic dystrophy 4;C3151186:Nephronophthisis 12 (1)

Jeune thoracic dystrophy;C0687120:Nephronophthisis (1)

not provided (1)

not specified (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.78

CADD

Benign

4.3

(source)

DANN

Benign

0.71

PhyloP100

-1.2

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.0

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over