2-208266272-A-T

Variant names:

• chr2-208266272-A-T
• rs1037223631
• NM_015040.4:c.-153A>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_015040.4(PIKFYVE):​c.-153A>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000197 in 151,900 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PIKFYVE NM_015040.4 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.934
• Publications: 0 publications found

Genes affected

PIKFYVE (HGNC:23785): (phosphoinositide kinase, FYVE-type zinc finger containing) Phosphorylated derivatives of phosphatidylinositol (PtdIns) regulate cytoskeletal functions, membrane trafficking, and receptor signaling by recruiting protein complexes to cell- and endosomal-membranes. Humans have multiple PtdIns proteins that differ by the degree and position of phosphorylation of the inositol ring. This gene encodes an enzyme (PIKfyve; also known as phosphatidylinositol-3-phosphate 5-kinase type III or PIPKIII) that phosphorylates the D-5 position in PtdIns and phosphatidylinositol-3-phosphate (PtdIns3P) to make PtdIns5P and PtdIns(3,5)biphosphate. The D-5 position also can be phosphorylated by type I PtdIns4P-5-kinases (PIP5Ks) that are encoded by distinct genes and preferentially phosphorylate D-4 phosphorylated PtdIns. In contrast, PIKfyve preferentially phosphorylates D-3 phosphorylated PtdIns. In addition to being a lipid kinase, PIKfyve also has protein kinase activity. PIKfyve regulates endomembrane homeostasis and plays a role in the biogenesis of endosome carrier vesicles from early endosomes. The protein plays a key role in cell entry of ebola virus and SARS-CoV-2 by endocytosis Mutations in this gene cause corneal fleck dystrophy (CFD); an autosomal dominant disorder characterized by numerous small white flecks present in all layers of the corneal stroma. Histologically, these flecks appear to be keratocytes distended with lipid and mucopolysaccharide filled intracytoplasmic vacuoles. [provided by RefSeq, Jul 2021]

IDH1 (HGNC:5382): (isocitrate dehydrogenase (NADP(+)) 1) Isocitrate dehydrogenases catalyze the oxidative decarboxylation of isocitrate to 2-oxoglutarate. These enzymes belong to two distinct subclasses, one of which utilizes NAD(+) as the electron acceptor and the other NADP(+). Five isocitrate dehydrogenases have been reported: three NAD(+)-dependent isocitrate dehydrogenases, which localize to the mitochondrial matrix, and two NADP(+)-dependent isocitrate dehydrogenases, one of which is mitochondrial and the other predominantly cytosolic. Each NADP(+)-dependent isozyme is a homodimer. The protein encoded by this gene is the NADP(+)-dependent isocitrate dehydrogenase found in the cytoplasm and peroxisomes. It contains the PTS-1 peroxisomal targeting signal sequence. The presence of this enzyme in peroxisomes suggests roles in the regeneration of NADPH for intraperoxisomal reductions, such as the conversion of 2, 4-dienoyl-CoAs to 3-enoyl-CoAs, as well as in peroxisomal reactions that consume 2-oxoglutarate, namely the alpha-hydroxylation of phytanic acid. The cytoplasmic enzyme serves a significant role in cytoplasmic NADPH production. Alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Sep 2013]

IDH1 Gene-Disease associations (from GenCC):

• Maffucci syndrome

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.79).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_015040.4. 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
	PIKFYVE	NM_015040.4	MANE Select	c.-153A>T		5_prime_UTR_premature_start_codon_gain	Exon 1 of 42	NP_055855.2	Q9Y2I7-1
	PIKFYVE	NM_015040.4	MANE Select	c.-153A>T		5_prime_UTR	Exon 1 of 42	NP_055855.2	Q9Y2I7-1
	PIKFYVE	NM_001178000.2		c.-153A>T		5_prime_UTR_premature_start_codon_gain	Exon 1 of 12	NP_001171471.1	Q9Y2I7-4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PIKFYVE	ENST00000264380.9	TSL:1 MANE Select	c.-153A>T		5_prime_UTR_premature_start_codon_gain	Exon 1 of 42	ENSP00000264380.4	Q9Y2I7-1
	PIKFYVE	ENST00000392202.7	TSL:1	c.-153A>T		5_prime_UTR_premature_start_codon_gain	Exon 1 of 10	ENSP00000376038.3	Q9Y2I7-2
	PIKFYVE	ENST00000264380.9	TSL:1 MANE Select	c.-153A>T		5_prime_UTR	Exon 1 of 42	ENSP00000264380.4	Q9Y2I7-1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 151900 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000242

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000194

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 92 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 74

African (AFR) AF: 0.00 AC: 0 AN: 2

American (AMR) AC: 0 AN: 0

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 2

East Asian (EAS) AF: 0.00 AC: 0 AN: 4

South Asian (SAS) AF: 0.00 AC: 0 AN: 4

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 2

Middle Eastern (MID) AC: 0 AN: 0

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 74

Other (OTH) AF: 0.00 AC: 0 AN: 4

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 151900 Hom.: 0 Cov.: 32 AF XY: 0.0000270 AC XY: 2 AN XY: 74152

African (AFR) AF: 0.0000242 AC: 1 AN: 41344

American (AMR) AF: 0.00 AC: 0 AN: 15248

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.000194 AC: 1 AN: 5152

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10544

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68006

Other (OTH) AF: 0.00 AC: 0 AN: 2086

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000302

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Fleck corneal dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.79
CADD	Benign	0.93
DANN	Benign	0.69
PhyloP100		-0.93
PromoterAI		-0.12	Neutral

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: rs1037223631; hg19: chr2-209130996;