19-48965344-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP5_Moderate

The NM_000146.4(FTL):c.-164C>A variant causes a 5 prime UTR change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: FTL NM_000146.4 5_prime_UTR
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 7.55

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 19-48965344-C-A is Pathogenic according to our data. Variant chr19-48965344-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 16481.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FTL	NM_000146.4	c.-164C>A		5_prime_UTR_variant	1/4	ENST00000331825.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FTL	ENST00000331825.11	c.-164C>A		5_prime_UTR_variant	1/4	1	NM_000146.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 525598 Hom.: 0 Cov.: 4 AF XY: 0.00 AC XY: 0 AN XY: 284060

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary hyperferritinemia with congenital cataracts Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Feb 19, 2013

- -

Hereditary hyperferritinemia with congenital cataracts;C1853578:Neuroferritinopathy Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Oct 11, 2020

The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This variant occurs in a non-coding region of the FTL gene. It does not change the encoded amino acid sequence of the FTL protein. For these reasons, this variant has been classified as Pathogenic. This nucleotide change is located in a region of the FTL 5'UTR where a significant number of previously reported deleterious variants has been observed (PMID: 19800271, 7493028, 23421845, 10383191, 22881709, 9226182), and the mechanism of action suggest that this c.-164C>A change is also likely to be deleterious. Experimental studies and prediction algorithms are not available for this specific variant (c.-164C>A), although studies indicate that other changes at this position (c.-164C>G, c.-164C>T, c.-164delC) disrupt binding of Iron Regulatory Proteins (IRPs) to the FTL 5' UTR (PMID: 2336358, 23421845). This variant has been observed in individual(s) with clinical features of hereditary hyperferritinemia-cataract syndrome (PMID: 9414313, Invitae). It has also been observed to segregate with disease in related individuals. This variant is also known as +36C>A. ClinVar contains an entry for this variant (Variation ID: 16481). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Uncertain	-0.040
Cadd	Benign	22
Dann	Benign	0.97

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: rs398124637; hg19: chr19-49468601;