10-103882785-G-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_024928.5(STN1):c.1006C>T(p.Arg336Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000297 in 1,613,986 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. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R336H) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000031 (0 hom.)
• Consequence: STN1 NM_024928.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.693

Genes affected

STN1 (HGNC:26200): (STN1 subunit of CST complex) OBFC1 and C17ORF68 (MIM 613129) are subunits of an alpha accessory factor (AAF) that stimulates the activity of DNA polymerase-alpha-primase (see MIM 176636), the enzyme that initiates DNA replication (Casteel et al., 2009 [PubMed 19119139]). OBFC1 also appears to function in a telomere-associated complex with C17ORF68 and TEN1 (C17ORF106; MIM 613130) (Miyake et al., 2009 [PubMed 19854130]).[supplied by OMIM, Nov 2009]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.06504965).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
STN1	NM_024928.5	c.1006C>T	p.Arg336Cys	missense_variant	10/10	ENST00000224950.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
STN1	ENST00000224950.8	c.1006C>T	p.Arg336Cys	missense_variant	10/10	1	NM_024928.5	P1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152204 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

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

GnomAD3 exomes AF: 0.0000562 AC: 14 AN: 248980 Hom.: 0 AF XY: 0.0000223 AC XY: 3 AN XY: 134542

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000383

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: 0.00000886

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000308 AC: 45 AN: 1461782 Hom.: 0 Cov.: 30 AF XY: 0.0000248 AC XY: 18 AN XY: 727194

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.000358

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000243

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152204 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74362

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000655

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000302

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.00 AC: 0

ExAC AF: 0.0000330 AC: 4

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 03, 2023

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 336 of the STN1 protein (p.Arg336Cys). This variant is present in population databases (rs761593090, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with STN1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1468946). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt STN1 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.071
BayesDel_addAF	Benign	-0.49	T
BayesDel_noAF	Benign	-0.62
Cadd	Benign	19
Dann	Uncertain	0.98
DEOGEN2	Benign	0.019	T;T
Eigen	Benign	-0.52
Eigen_PC	Benign	-0.66
FATHMM_MKL	Benign	0.31	N
M_CAP	Benign	0.014	T
MetaRNN	Benign	0.065	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.6	L;L
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.23	T
PROVEAN	Benign	-0.67	N;N
REVEL	Benign	0.14
Sift	Benign	0.051	T;T
Sift4G	Uncertain	0.045	D;D
Polyphen		0.95	P;P
Vest4		0.086
MutPred		0.33		Loss of phosphorylation at S334 (P = 0.0971);Loss of phosphorylation at S334 (P = 0.0971);
MVP		0.15
MPC		0.19
ClinPred		0.077	T
GERP RS		-5.4
Varity_R		0.071
gMVP		0.28

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

LitVar

Other links and lift over

dbSNP: rs761593090; hg19: chr10-105642543; COSMIC: COSV105043131; COSMIC: COSV105043131;