9-69064936-A-G

Variant names:

• chr9-69064936-A-G
• rs140987490
• NM_000144.5:c.385-2A>G

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_000144.5(FXN):​c.385-2A>G variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: FXN NM_000144.5 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 8.68
• Publications: 1 publications found

Genes affected

FXN (HGNC:3951): (frataxin) This nuclear gene encodes a mitochondrial protein which belongs to the FRATAXIN family. The protein functions in regulating mitochondrial iron transport and respiration. The expansion of intronic trinucleotide repeat GAA from 8-33 repeats to >90 repeats results in Friedreich ataxia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2016]

FXN Gene-Disease associations (from GenCC):

• Friedreich ataxia

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• Friedreich ataxia 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• Friedreich ataxia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000285130 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 9-69064936-A-G is Pathogenic according to our data. Variant chr9-69064936-A-G is described in ClinVar as Pathogenic. ClinVar VariationId is 3980.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FXN	NM_000144.5	c.385-2A>G		splice_acceptor_variant, intron_variant	Intron 3 of 4	ENST00000484259.3	NP_000135.2
FXN	NM_181425.3	c.385-2A>G		splice_acceptor_variant, intron_variant	Intron 3 of 4		NP_852090.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FXN	ENST00000484259.3	c.385-2A>G		splice_acceptor_variant, intron_variant	Intron 3 of 4	3	NM_000144.5	ENSP00000419243.2
ENSG00000285130	ENST00000642889.1	c.165+28989A>G		intron_variant	Intron 1 of 24			ENSP00000493780.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Friedreich ataxia Pathogenic:1

Mar 08, 1996

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.25
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		8.7
GERP RS		5.5
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.50		Position offset: 4
DS_AL_spliceai		0.98		Position offset: 2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs140987490; hg19: chr9-71679852;