16-88707137-C-T

Variant summary

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

The NM_001012759.3(CTU2):c.70C>T(p.Arg24Cys) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000459 in 1,613,626 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000050 (0 hom.)
• Consequence: CTU2 NM_001012759.3 missense, splice_region
• Scores: Splicing: ADA: 0.00005559
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.817

Genes affected

CTU2 (HGNC:28005): (cytosolic thiouridylase subunit 2) This gene encodes a protein which is involved in the post-transcriptional modification of transfer RNAs (tRNAs). The encoded protein plays a role in thiolation of uridine residue present at the wobble position in a subset of tRNAs, resulting in enhanced codon reading accuracy. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2016]

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=0.053893954).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CTU2	NM_001012759.3	c.70C>T	p.Arg24Cys	missense_variant, splice_region_variant	2/15	ENST00000453996.7
CTU2	NM_001318507.2	c.70C>T	p.Arg24Cys	missense_variant, splice_region_variant	2/15
CTU2	NM_001012762.3	c.70C>T	p.Arg24Cys	missense_variant, splice_region_variant	2/14
CTU2	NM_001318513.2	c.-113C>T		splice_region_variant, 5_prime_UTR_variant	2/14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CTU2	ENST00000453996.7	c.70C>T	p.Arg24Cys	missense_variant, splice_region_variant	2/15	1	NM_001012759.3	P2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152132 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000239 AC: 6 AN: 250926 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135824

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000353

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000499 AC: 73 AN: 1461494 Hom.: 0 Cov.: 32 AF XY: 0.0000509 AC XY: 37 AN XY: 727014

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000126

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000540

Gnomad4 OTH exome AF: 0.0000662

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152132 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74318

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000868 Hom.: 0

Bravo AF: 0.0000189

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 21, 2022

The c.70C>T (p.R24C) alteration is located in exon 2 (coding exon 2) of the CTU2 gene. This alteration results from a C to T substitution at nucleotide position 70, causing the arginine (R) at amino acid position 24 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.43	T
BayesDel_noAF	Benign	-0.68
Cadd	Benign	13
Dann	Benign	0.87
DEOGEN2	Benign	0.028	T;.;.
Eigen	Benign	-1.3
Eigen_PC	Benign	-1.4
FATHMM_MKL	Benign	0.026	N
LIST_S2	Benign	0.72	T;T;T
M_CAP	Benign	0.019	T
MetaRNN	Benign	0.054	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-0.020	N;N;.
MutationTaster	Benign	1.0	D;N;N;N
PrimateAI	Uncertain	0.74	T
PROVEAN	Benign	-1.3	N;N;N
REVEL	Benign	0.013
Sift	Benign	0.21	T;T;T
Sift4G	Benign	0.18	T;T;T
Polyphen		0.0010	B;B;.
Vest4		0.20
MVP		0.17
ClinPred		0.045	T
GERP RS		-4.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.12
gMVP		0.39

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000056
dbscSNV1_RF	Benign	0.0
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: rs372179688; hg19: chr16-88773545;