2-15942038-C-T

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4_Strong BS1_Supporting BS2

The NM_005378.6(MYCN):c.-27C>T variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000036 in 1,612,882 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 0.000072 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000032 (0 hom.)
• Consequence: MYCN NM_005378.6 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.766

Genes affected

MYCN (HGNC:7559): (MYCN proto-oncogene, bHLH transcription factor) This gene is a member of the MYC family and encodes a protein with a basic helix-loop-helix (bHLH) domain. This protein is located in the nucleus and must dimerize with another bHLH protein in order to bind DNA. Amplification of this gene is associated with a variety of tumors, most notably neuroblastomas. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2014]

MYCNOS (HGNC:16911): (MYCN opposite strand) This gene is transcribed in antisense to the v-myc avian myelocytomatosis viral oncogene neuroblastoma derived homolog gene (MYCN). It is thought to encode a small, novel protein that stabilizes MYCN, prevents apoptosis, and promotes cell proliferation. Transcripts at this locus may also act directly as functional RNAs to recruit transcriptional regulators to the promoter of MYCN and stimulate transcription of this oncogene. This gene therefore functions through both RNA and protein products. [provided by RefSeq, Aug 2016]

ACMG classification

Verdict is Benign. Variant got -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.85).
• BS1: Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.0000723 (11/152168) while in subpopulation AMR AF= 0.000262 (4/15290). AF 95% confidence interval is 0.0000887. There are 0 homozygotes in gnomad4. There are 4 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
• BS2: High AC in GnomAd at 11 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYCN	NM_005378.6	c.-27C>T		5_prime_UTR_variant	2/3	ENST00000281043.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYCN	ENST00000281043.4	c.-27C>T		5_prime_UTR_variant	2/3	5	NM_005378.6	P1
MYCN	ENST00000638417.1	c.157+1295C>T		intron_variant		2
MYCNOS	ENST00000641534.1	n.98+114G>A		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes AF: 0.0000723 AC: 11 AN: 152168 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000965

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000262

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000610 AC: 15 AN: 245910 Hom.: 0 AF XY: 0.0000299 AC XY: 4 AN XY: 133708

Gnomad AFR exome AF: 0.0000635

Gnomad AMR exome AF: 0.000116

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000655

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000183

Gnomad OTH exome AF: 0.000994

GnomAD4 exome AF: 0.0000322 AC: 47 AN: 1460714 Hom.: 0 Cov.: 31 AF XY: 0.0000220 AC XY: 16 AN XY: 726634

Gnomad4 AFR exome AF: 0.0000598

Gnomad4 AMR exome AF: 0.0000895

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000504

Gnomad4 SAS exome AF: 0.0000348

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000216

Gnomad4 OTH exome AF: 0.000199

GnomAD4 genome AF: 0.0000723 AC: 11 AN: 152168 Hom.: 0 Cov.: 33 AF XY: 0.0000538 AC XY: 4 AN XY: 74326

Gnomad4 AFR AF: 0.0000965

Gnomad4 AMR AF: 0.000262

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000868 Hom.: 0

Bravo AF: 0.0000416

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

MYCN-related disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Dec 28, 2023

The MYCN c.248C>T variant is predicted to result in the amino acid substitution p.Pro83Leu. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.017% of alleles in individuals of Latino descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.85
Cadd	Benign	1.4
Dann	Benign	0.94

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: rs769956590; hg19: chr2-16082160; COSMIC: COSV55257829; COSMIC: COSV55257829;