rs148698100

Variant names:

• chr9-69053230-C-G
• rs148698100
• NM_000144.5:c.354C>G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_000144.5(FXN):​c.354C>G​(p.Tyr118*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 31)
• Consequence: FXN NM_000144.5 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.140
• Publications: 3 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 10 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FXN	NM_000144.5	c.354C>G	p.Tyr118*	stop_gained	Exon 3 of 5	ENST00000484259.3	NP_000135.2
FXN	NM_181425.3	c.354C>G	p.Tyr118*	stop_gained	Exon 3 of 5		NP_852090.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FXN	ENST00000484259.3	c.354C>G	p.Tyr118*	stop_gained	Exon 3 of 5	3	NM_000144.5	ENSP00000419243.2
ENSG00000285130	ENST00000642889.1	c.165+17283C>G		intron_variant	Intron 1 of 24			ENSP00000493780.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.37
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Uncertain	0.24
Eigen_PC	Benign	-0.013
FATHMM_MKL	Benign	0.67	D
PhyloP100		-0.14
Vest4		0.50, 0.56, 0.53
GERP RS		0.16
Mutation Taster		=0/200	disease causing (fs/PTC)

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

Other links and lift over

dbSNP: rs148698100; hg19: chr9-71668146;