rs1554554240

Positions:

• chr8-89937041-G-A
• chr8-89937041-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_002485.5(NBN):​c.2219C>T​(p.Ala740Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A740D) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NBN NM_002485.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.31

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 Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.765

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NBN	NM_002485.5	c.2219C>T	p.Ala740Val	missense_variant	15/16	ENST00000265433.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NBN	ENST00000265433.8	c.2219C>T	p.Ala740Val	missense_variant	15/16	1	NM_002485.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Microcephaly, normal intelligence and immunodeficiency Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Oct 24, 2017	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.77
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Pathogenic	27
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.16	T;T;.
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.94	D;D;D
M_CAP	Uncertain	0.15	D
MetaRNN	Pathogenic	0.77	D;D;D
MetaSVM	Uncertain	-0.088	T
MutationAssessor	Uncertain	2.3	M;.;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.61	T
PROVEAN	Benign	-2.3	N;N;.
REVEL	Uncertain	0.39
Sift	Uncertain	0.0060	D;D;.
Sift4G	Uncertain	0.013	D;D;D
Polyphen		1.0	D;.;.
Vest4		0.85
MutPred		0.64		Loss of helix (P = 0.0304);.;.;
MVP		0.88
MPC		0.41
ClinPred		0.99	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.36
gMVP		0.37

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.10		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: rs1554554240; hg19: chr8-90949269; COSMIC: COSV55373431;