17-8231740-C-T

Position:

• chr17-8231740-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_025099.6(CTC1):​c.2461G>A​(p.Ala821Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,716 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign 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. A821S) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CTC1 NM_025099.6 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.793

Genes affected

CTC1 (HGNC:26169): (CST telomere replication complex component 1) This gene encodes a component of the CST complex. This complex plays an essential role in protecting telomeres from degradation. This protein also forms a heterodimer with the CST complex subunit STN1 to form the enzyme alpha accessory factor. This enzyme regulates DNA replication. Mutations in this gene are the cause of cerebroretinal microangiopathy with calcifications and cysts. Alternate splicing results in both coding and non-coding variants. [provided by RefSeq, Mar 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.20963997).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CTC1	NM_025099.6	c.2461G>A	p.Ala821Thr	missense_variant	14/23	ENST00000651323.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CTC1	ENST00000651323.1	c.2461G>A	p.Ala821Thr	missense_variant	14/23		NM_025099.6	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000401 AC: 1 AN: 249520 Hom.: 0 AF XY: 0.00000739 AC XY: 1 AN XY: 135394

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000883

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461716 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 727164

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Benign	0.0068	T
BayesDel_noAF	Benign	-0.23
CADD	Benign	18
DANN	Benign	0.88
DEOGEN2	Uncertain	0.56	D
Eigen	Benign	-0.077
Eigen_PC	Benign	-0.10
FATHMM_MKL	Benign	0.15	N
LIST_S2	Benign	0.63	T
M_CAP	Benign	0.030	D
MetaRNN	Benign	0.21	T
MetaSVM	Uncertain	-0.22	T
MutationAssessor	Uncertain	2.5	M
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.32	T
PROVEAN	Benign	-1.5	N
REVEL	Uncertain	0.29
Sift	Benign	0.051	T
Sift4G	Benign	0.070	T
Polyphen		0.57	P
Vest4		0.10
MutPred		0.34		Gain of phosphorylation at A821 (P = 0.029);
MVP		0.73
MPC		0.13
ClinPred		0.17	T
GERP RS		3.5
Varity_R		0.16
gMVP		0.34

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

LitVar

Other links and lift over

dbSNP: rs771475755; hg19: chr17-8135058;