chr22-32395072-G-A

Position:

• chr22-32395072-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_014306.5(RTCB):​c.1133C>T​(p.Thr378Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: RTCB NM_014306.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.89

Genes affected

RTCB (HGNC:26935): (RNA 2',3'-cyclic phosphate and 5'-OH ligase) Enables RNA ligase (ATP) activity and vinculin binding activity. Involved in tRNA splicing, via endonucleolytic cleavage and ligation. Located in cytosol and nucleoplasm. Part of tRNA-splicing ligase complex. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.963

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RTCB	NM_014306.5	c.1133C>T	p.Thr378Ile	missense_variant	9/12	ENST00000216038.6	NP_055121.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RTCB	ENST00000216038.6	c.1133C>T	p.Thr378Ile	missense_variant	9/12	1	NM_014306.5	ENSP00000216038	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

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

Oct 25, 2023

The c.1133C>T (p.T378I) alteration is located in exon 9 (coding exon 9) of the RTCB gene. This alteration results from a C to T substitution at nucleotide position 1133, causing the threonine (T) at amino acid position 378 to be replaced by an isoleucine (I). 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	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.20
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.30	T
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Benign	0.031	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Benign	-0.67	T
MutationAssessor	Uncertain	2.5	M
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-5.7	D
REVEL	Pathogenic	0.67
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.96
MutPred		0.89		Loss of disorder (P = 0.0312);
MVP		0.54
MPC		1.2
ClinPred		1.0	D
GERP RS		4.8
Varity_R		0.80
gMVP		0.97

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: rs1048524937; hg19: chr22-32791059;