22-20116431-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_001278639.2(RANBP1):c.246+1G>C variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,372 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: RANBP1 NM_001278639.2 splice_donor
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.38

Genes affected

RANBP1 (HGNC:9847): (RAN binding protein 1) This gene encodes a protein that forms a complex with Ras-related nuclear protein (Ran) and metabolizes guanoside triphosphate (GTP). This complex participates in the regulation of the cell cycle by controlling transport of proteins and nucleic acids into the nucleus. There are multiple pseudogenes for this gene on chromosomes 9, 12, 17, and X. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]

TRMT2A (HGNC:24974): (tRNA methyltransferase 2 homolog A) The protein encoded by this gene is of unknown function. However, it is orthologous to the mouse Trmt2a gene and contains an RNA methyltransferase domain. Expression of this gene varies during the cell cycle, with aberrant expression being a possible biomarker in certain breast cancers. Several transcript variants encoding two different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.38948625 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RANBP1	NM_001278639.2	c.246+1G>C		splice_donor_variant		ENST00000430524.6
TRMT2A	NM_022727.6	c.206C>G	p.Thr69Ser	missense_variant	2/12	ENST00000252136.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RANBP1	ENST00000430524.6	c.246+1G>C		splice_donor_variant		3	NM_001278639.2	A2
TRMT2A	ENST00000252136.12	c.206C>G	p.Thr69Ser	missense_variant	2/12	1	NM_022727.6	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000404 AC: 1 AN: 247466 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 134926

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: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460372 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 726432

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

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.206C>G (p.T69S) alteration is located in exon 2 (coding exon 2) of the TRMT2A gene. This alteration results from a C to G substitution at nucleotide position 206, causing the threonine (T) at amino acid position 69 to be replaced by a serine (S). 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	0.62
BayesDel_addAF	Uncertain	0.077	D
BayesDel_noAF	Benign	-0.21
Cadd	Pathogenic	29
Dann	Uncertain	0.99
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Pathogenic	1.0	D
M_CAP	Benign	0.049	D
MutationTaster	Benign	1.0	D;D;D;D;D
ClinPred		0.86	D
GERP RS		5.6

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs1281360817; hg19: chr22-20103954;