5-6599910-G-A

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BS1_Supporting

The NM_017755.6(NSUN2):c.*16C>T variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000436 in 1,605,998 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00015 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000032 (0 hom.)
• Consequence: NSUN2 NM_017755.6 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.26

Genes affected

NSUN2 (HGNC:25994): (NOP2/Sun RNA methyltransferase 2) This gene encodes a methyltransferase that catalyzes the methylation of cytosine to 5-methylcytosine (m5C) at position 34 of intron-containing tRNA(Leu)(CAA) precursors. This modification is necessary to stabilize the anticodon-codon pairing and correctly translate the mRNA. Alternatively spliced transcript variants encoding different isoforms have been noted for this gene.[provided by RefSeq, Mar 2011]

LINC01018 (HGNC:27394): (long intergenic non-protein coding RNA 1018)

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.91).
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000151 (23/152202) while in subpopulation AFR AF= 0.000531 (22/41434). AF 95% confidence interval is 0.000359. There are 0 homozygotes in gnomad4. There are 15 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NSUN2	NM_017755.6	c.*16C>T		3_prime_UTR_variant	19/19	ENST00000264670.11
NSUN2	NM_001193455.2	c.*16C>T		3_prime_UTR_variant	18/18
NSUN2	NR_037947.2	n.2300C>T		non_coding_transcript_exon_variant	18/18

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NSUN2	ENST00000264670.11	c.*16C>T		3_prime_UTR_variant	19/19	1	NM_017755.6	P2
LINC01018	ENST00000661215.1	n.757-211G>A		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes AF: 0.000151 AC: 23 AN: 152202 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.000531

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

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: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000603 AC: 15 AN: 248848 Hom.: 0 AF XY: 0.0000595 AC XY: 8 AN XY: 134558

Gnomad AFR exome AF: 0.000492

Gnomad AMR exome AF: 0.0000291

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: 0.0000531

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000323 AC: 47 AN: 1453796 Hom.: 0 Cov.: 31 AF XY: 0.0000277 AC XY: 20 AN XY: 722548

Gnomad4 AFR exome AF: 0.000420

Gnomad4 AMR exome AF: 0.0000449

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000253

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000235

Gnomad4 OTH exome AF: 0.0000500

GnomAD4 genome AF: 0.000151 AC: 23 AN: 152202 Hom.: 0 Cov.: 33 AF XY: 0.000202 AC XY: 15 AN XY: 74366

Gnomad4 AFR AF: 0.000531

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.000257

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability, autosomal recessive 5 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.91
Cadd	Benign	1.3
Dann	Benign	0.50

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: rs368107079; hg19: chr5-6600023;