rs993307430

chrX-14850514-G-AchrX-14850514-G-C

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BP4

The NM_001018113.3(FANCB):c.1487C>T(p.Ser496Phe) variant causes a missense change. The variant allele was found at a frequency of 0.00000184 in 1,087,125 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 2 hemizygotes in GnomAD. In-silico tool predicts a benign 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. S496C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 0.0000018 (0 hom. 2 hem.)
• Consequence: FANCB NM_001018113.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.62

Genes affected

FANCB (HGNC:3583): (FA complementation group B) This gene encodes a member of the Fanconi anemia complementation group B. This protein is assembled into a nucleoprotein complex that is involved in the repair of DNA lesions. Mutations in this gene can cause chromosome instability and VACTERL syndrome with hydrocephalus. [provided by RefSeq, Apr 2016]

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.388739).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FANCB	NM_001018113.3	c.1487C>T	p.Ser496Phe	missense_variant	7/10	ENST00000650831.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FANCB	ENST00000650831.1	c.1487C>T	p.Ser496Phe	missense_variant	7/10		NM_001018113.3	P2

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 0.00000184 AC: 2 AN: 1087125 Hom.: 0 Cov.: 28 AF XY: 0.00000566 AC XY: 2 AN XY: 353579

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: 0.0000186

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000120

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 23

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Fanconi anemia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 01, 2021

This sequence change replaces serine with phenylalanine at codon 496 of the FANCB protein (p.Ser496Phe). The serine residue is weakly conserved and there is a large physicochemical difference between serine and phenylalanine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with FANCB-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Uncertain	0.032	T
BayesDel_noAF	Benign	-0.19
Cadd	Benign	22
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.56	D;D;T
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.79	T;.;T
M_CAP	Benign	0.021	T
MetaRNN	Benign	0.39	T;T;T
MetaSVM	Uncertain	-0.20	T
MutationAssessor	Uncertain	2.6	M;M;.
MutationTaster	Benign	0.61	D;D
PrimateAI	Benign	0.36	T
PROVEAN	Uncertain	-3.9	D;D;D
REVEL	Benign	0.27
Sift	Uncertain	0.0010	D;D;D
Sift4G	Uncertain	0.054	T;T;T
Polyphen		1.0	D;D;.
Vest4		0.29
MutPred		0.37		Loss of disorder (P = 0.0077);Loss of disorder (P = 0.0077);Loss of disorder (P = 0.0077);
MVP		0.36
MPC		0.53
ClinPred		0.99	D
GERP RS		4.7
Varity_R		0.65

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs993307430; hg19: chrX-14868636;