rs76726265

Variant names:

• chr2-165901879-C-G
• NM_024753.5:c.2600G>C

Your query was ambiguous. Multiple possible variants found:

• chr2-165901879-C-G
• chr2-165901879-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PM5 PP3_Moderate

The NM_024753.5(TTC21B):​c.2600G>C​(p.Arg867Pro) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic 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. R867C) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TTC21B NM_024753.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.14

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.849

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TTC21B	NM_024753.5	c.2600G>C	p.Arg867Pro	missense_variant	Exon 20 of 29	ENST00000243344.8	NP_079029.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TTC21B	ENST00000243344.8	c.2600G>C	p.Arg867Pro	missense_variant	Exon 20 of 29	1	NM_024753.5	ENSP00000243344.7

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.23
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.51	D
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Benign	0.051	D
MetaRNN	Pathogenic	0.85	D
MetaSVM	Uncertain	-0.10	T
MutationAssessor	Pathogenic	2.9	M
PrimateAI	Uncertain	0.69	T
PROVEAN	Pathogenic	-5.9	D
REVEL	Uncertain	0.51
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.85
MutPred		0.49		Loss of MoRF binding (P = 0.001);
MVP		0.44
MPC		0.27
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.94
gMVP		0.80

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: chr2-166758389;