chr19-48966341-G-T

Variant names:

• chr19-48966341-G-T
• rs199869995
• NM_000146.4:c.310G>T

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 10P and 5B. PVS1 PP5_Moderate BS1_Supporting BS2

The NM_000146.4(FTL):​c.310G>T​(p.Glu104*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000137 in 1,461,864 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 Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: FTL NM_000146.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 9.68
• Publications: 7 publications found

Genes affected

FTL (HGNC:3999): (ferritin light chain) This gene encodes the light subunit of the ferritin protein. Ferritin is the major intracellular iron storage protein in prokaryotes and eukaryotes. It is composed of 24 subunits of the heavy and light ferritin chains. Variation in ferritin subunit composition may affect the rates of iron uptake and release in different tissues. A major function of ferritin is the storage of iron in a soluble and nontoxic state. Defects in this light chain ferritin gene are associated with several neurodegenerative diseases and hyperferritinemia-cataract syndrome. This gene has multiple pseudogenes. [provided by RefSeq, Jul 2008]

FTL Gene-Disease associations (from GenCC):

• hereditary hyperferritinemia with congenital cataracts

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• neuroferritinopathy

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet, Genomics England PanelApp
• L-ferritin deficiency

  Inheritance: Unknown, AD Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
• genetic hyperferritinemia without iron overload

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 19-48966341-G-T is Pathogenic according to our data. Variant chr19-48966341-G-T is described in ClinVar as Pathogenic. ClinVar VariationId is 96690.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population sas. GnomAdExome4 allele frequency = 0.0000137 (20/1461864) while in subpopulation SAS AF = 0.000185 (16/86254). AF 95% confidence interval is 0.000115. There are 0 homozygotes in GnomAdExome4. There are 15 alleles in the male GnomAdExome4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High AC in GnomAdExome4 at 20 Unknown,AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000146.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FTL	NM_000146.4	MANE Select	c.310G>T	p.Glu104*	stop_gained	Exon 3 of 4	NP_000137.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FTL	ENST00000331825.11	TSL:1 MANE Select	c.310G>T	p.Glu104*	stop_gained	Exon 3 of 4	ENSP00000366525.2	P02792
	FTL	ENST00000853542.1		c.325G>T	p.Glu109*	stop_gained	Exon 3 of 4	ENSP00000523601.1
	FTL	ENST00000853538.1		c.307G>T	p.Glu103*	stop_gained	Exon 3 of 4	ENSP00000523597.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.0000159 AC: 4 AN: 251406 AF XY: 0.0000294

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000264

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000137 AC: 20 AN: 1461864 Hom.: 0 Cov.: 32 AF XY: 0.0000206 AC XY: 15 AN XY: 727230

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.000185 AC: 16 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1112004

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000515 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.0000247 AC: 3

EpiCase AF: 0.00

EpiControl AF: 0.000119

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Inborn genetic diseases (1)
1	-	-	L-FERRITIN DEFICIENCY, AUTOSOMAL RECESSIVE (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	41
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		9.7
Vest4		0.88
GERP RS		4.5
Mutation Taster		=19/181	disease causing (ClinVar)

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: rs199869995; hg19: chr19-49469598;