chr16-89783098-T-A

Position:

• chr16-89783098-T-A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_000135.4(FANCA):​c.1475A>T​(p.His492Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000048 in 1,459,706 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. H492R) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: FANCA NM_000135.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:2
• Conservation: PhyloP100: 6.31

Genes affected

FANCA (HGNC:3582): (FA complementation group A) The Fanconi anemia complementation group (FANC) currently includes FANCA, FANCB, FANCC, FANCD1 (also called BRCA2), FANCD2, FANCE, FANCF, FANCG, FANCI, FANCJ (also called BRIP1), FANCL, FANCM and FANCN (also called PALB2). The previously defined group FANCH is the same as FANCA. Fanconi anemia is a genetically heterogeneous recessive disorder characterized by cytogenetic instability, hypersensitivity to DNA crosslinking agents, increased chromosomal breakage, and defective DNA repair. The members of the Fanconi anemia complementation group do not share sequence similarity; they are related by their assembly into a common nuclear protein complex. This gene encodes the protein for complementation group A. Alternative splicing results in multiple transcript variants encoding different isoforms. Mutations in this gene are the most common cause of Fanconi anemia. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-89783098-T-C is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.95

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FANCA	NM_000135.4	c.1475A>T	p.His492Leu	missense_variant	16/43	ENST00000389301.8	NP_000126.2
FANCA	NM_001286167.3	c.1475A>T	p.His492Leu	missense_variant	16/43		NP_001273096.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FANCA	ENST00000389301.8	c.1475A>T	p.His492Leu	missense_variant	16/43	1	NM_000135.4	ENSP00000373952	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251284 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135842

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

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: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000480 AC: 7 AN: 1459706 Hom.: 0 Cov.: 33 AF XY: 0.00000551 AC XY: 4 AN XY: 726260

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000540

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Fanconi anemia complementation group A Pathogenic:1 Uncertain:1

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Pathogenic, no assertion criteria provided	curation	Leiden Open Variation Database	Feb 28, 2020	Curator: Arleen D. Auerbach. Submitter to LOVD: Arleen D. Auerbach. -

Fanconi anemia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 31, 2021

This sequence change replaces histidine with leucine at codon 492 of the FANCA protein (p.His492Leu). The histidine residue is highly conserved and there is a moderate physicochemical difference between histidine and leucine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with FANCA-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: "Benign"; 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	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.53
CADD	Uncertain	24
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.73	D;.
Eigen	Uncertain	0.67
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.86	D;D
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.95	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.7	M;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.54	T
PROVEAN	Pathogenic	-9.4	D;D
REVEL	Pathogenic	0.91
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.91
MutPred		0.68		Loss of sheet (P = 0.1158);Loss of sheet (P = 0.1158);
MVP		1.0
ClinPred		0.99	D
GERP RS		5.5
Varity_R		0.88
gMVP		0.87

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: rs925457555; hg19: chr16-89849506;