8-89978341-T-C

Position:

• chr8-89978341-T-C

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_Strong BP6 BS1 BS2

The NM_002485.5(NBN):​c.481-18A>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000616 in 1,575,712 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000033 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000065 (2 hom.)
• Consequence: NBN NM_002485.5 intron
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:2
• Conservation: PhyloP100: -0.592

Genes affected

NBN (HGNC:7652): (nibrin) Mutations in this gene are associated with Nijmegen breakage syndrome, an autosomal recessive chromosomal instability syndrome characterized by microcephaly, growth retardation, immunodeficiency, and cancer predisposition. The encoded protein is a member of the MRE11/RAD50 double-strand break repair complex which consists of 5 proteins. This gene product is thought to be involved in DNA double-strand break repair and DNA damage-induced checkpoint activation. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Benign. Variant got -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BP6: Variant 8-89978341-T-C is Benign according to our data. Variant chr8-89978341-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 138429.We mark this variant Likely_benign, oryginal submissions are: {Benign=2, Uncertain_significance=1}.
• BS1: Variant frequency is greater than expected in population amr. gnomad4_exome allele frequency = 0.0000646 (92/1423540) while in subpopulation AMR AF= 0.00125 (56/44638). AF 95% confidence interval is 0.000991. There are 2 homozygotes in gnomad4_exome. There are 38 alleles in male gnomad4_exome subpopulation. Median coverage is 27. This position pass quality control queck.
• BS2: High Homozygotes in GnomAdExome4 at 2 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NBN	NM_002485.5	c.481-18A>G		intron_variant		ENST00000265433.8	NP_002476.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NBN	ENST00000265433.8	c.481-18A>G		intron_variant		1	NM_002485.5	ENSP00000265433	P1

Frequencies

GnomAD3 genomes AF: 0.0000329 AC: 5 AN: 152172 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000196

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000211 AC: 53 AN: 250626 Hom.: 2 AF XY: 0.000148 AC XY: 20 AN XY: 135544

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00125

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: 0.00

Gnomad OTH exome AF: 0.00164

GnomAD4 exome AF: 0.0000646 AC: 92 AN: 1423540 Hom.: 2 Cov.: 27 AF XY: 0.0000535 AC XY: 38 AN XY: 710242

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00125

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000269

Gnomad4 OTH exome AF: 0.000118

GnomAD4 genome AF: 0.0000329 AC: 5 AN: 152172 Hom.: 0 Cov.: 33 AF XY: 0.0000403 AC XY: 3 AN XY: 74350

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.000196

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.000113

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 03, 2015

The c.481-18A>G intronic alteration consists of a A to G substitution 18 nucleotides before coding exon 5 in the NBN gene. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not specified Benign:1

Benign, criteria provided, single submitter

clinical testing

GeneDx

Mar 24, 2014

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Microcephaly, normal intelligence and immunodeficiency Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 17, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	0.97
DANN	Benign	0.77

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: rs587781092; hg19: chr8-90990569;