6-109796856-G-A

Variant names:

• chr6-109796856-G-A
• rs1060501401
• NM_014845.6:c.2546+5G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_014845.6(FIG4):​c.2546+5G>A variant causes a splice region, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: FIG4 NM_014845.6 splice_region, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.84
• Publications: 0 publications found

Genes affected

FIG4 (HGNC:16873): (FIG4 phosphoinositide 5-phosphatase) The protein encoded by this gene belongs to the SAC domain-containing protein gene family. The SAC domain, approximately 400 amino acids in length and consisting of seven conserved motifs, has been shown to possess phosphoinositide phosphatase activity. The yeast homolog, Sac1p, is involved in the regulation of various phosphoinositides, and affects diverse cellular functions such as actin cytoskeleton organization, Golgi function, and maintenance of vacuole morphology. Membrane-bound phosphoinositides function as signaling molecules and play a key role in vesicle trafficking in eukaryotic cells. Mutations in this gene have been associated with Charcot-Marie-Tooth disease, type 4J. [provided by RefSeq, Jul 2008]

FIG4 Gene-Disease associations (from GenCC):

• Charcot-Marie-Tooth disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, Illumina
• Charcot-Marie-Tooth disease type 4J

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics, Laboratory for Molecular Medicine
• Yunis-Varon syndrome

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P
• amyotrophic lateral sclerosis type 11

  Inheritance: Unknown, AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp
• amyotrophic lateral sclerosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• bilateral parasagittal parieto-occipital polymicrogyria

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FIG4	NM_014845.6	c.2546+5G>A		splice_region_variant, intron_variant	Intron 22 of 22	ENST00000230124.8	NP_055660.1
FIG4	XM_011536281.4	c.2483+5G>A		splice_region_variant, intron_variant	Intron 22 of 22		XP_011534583.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FIG4	ENST00000230124.8	c.2546+5G>A		splice_region_variant, intron_variant	Intron 22 of 22	1	NM_014845.6	ENSP00000230124.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1351508 Hom.: 0 Cov.: 22 AF XY: 0.00 AC XY: 0 AN XY: 678330

African (AFR) AF: 0.00 AC: 0 AN: 31462

American (AMR) AF: 0.00 AC: 0 AN: 44600

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25492

East Asian (EAS) AF: 0.00 AC: 0 AN: 39162

South Asian (SAS) AF: 0.00 AC: 0 AN: 84022

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53350

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5586

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1011138

Other (OTH) AF: 0.00 AC: 0 AN: 56696

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Charcot-Marie-Tooth disease type 4 Uncertain:1

Sep 26, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change falls in intron 22 of the FIG4 gene. It does not directly change the encoded amino acid sequence of the FIG4 protein, but it affects a nucleotide within the consensus splice site of the intron. This variant is not present in population databases (ExAC no frequency). Nucleotide substitutions within the consensus splice site are relatively common causes of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of nucleotide changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. In summary, this is a novel intronic change with uncertain impact on splicing. It has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.25
CADD	Benign	22
DANN	Benign	0.94
PhyloP100		6.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.98
SpliceAI score (max)		0.72		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.72		Position offset: -5

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

Other links and lift over

dbSNP: rs1060501401; hg19: chr6-110118059;