17-5020079-G-A

Position:

• chr17-5020079-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_006612.6(KIF1C):​c.1750G>A​(p.Gly584Arg) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 16/25 in silico tools predict a damaging 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)
• Consequence: KIF1C NM_006612.6 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.08

Genes affected

KIF1C (HGNC:6317): (kinesin family member 1C) The protein encoded by this gene is a member of the kinesin-like protein family. The family members are microtubule-dependent molecular motors that transport organelles within cells and move chromosomes during cell division. Mutations in this gene are a cause of spastic ataxia 2, autosomal recessive. [provided by RefSeq, May 2014]

KIF1C-AS1 (HGNC:40324): (KIF1C antisense RNA 1)

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.937

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KIF1C	NM_006612.6	c.1750G>A	p.Gly584Arg	missense_variant, splice_region_variant	19/23	ENST00000320785.10	NP_006603.2
KIF1C	XM_005256424.3	c.1750G>A	p.Gly584Arg	missense_variant, splice_region_variant	20/24		XP_005256481.1
KIF1C-AS1	NR_120665.2	n.15C>T		non_coding_transcript_exon_variant	1/2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KIF1C	ENST00000320785.10	c.1750G>A	p.Gly584Arg	missense_variant, splice_region_variant	19/23	1	NM_006612.6	ENSP00000320821.5
KIF1C-AS1	ENST00000438266.1	n.15C>T		non_coding_transcript_exon_variant	1/2	2
KIF1C	ENST00000573815.1	n.292G>A		splice_region_variant, non_coding_transcript_exon_variant	3/6	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Spastic ataxia 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 21, 2022

This variant has not been reported in the literature in individuals affected with KIF1C-related conditions. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 584 of the KIF1C protein (p.Gly584Arg). This variant also falls at the last nucleotide of exon 19, which is part of the consensus splice site for this exon. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.92
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.46
CADD	Pathogenic	35
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.85	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.29	D
MetaRNN	Pathogenic	0.94	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.3	H
PrimateAI	Pathogenic	0.83	D
PROVEAN	Pathogenic	-7.3	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.62
MutPred		0.90		Gain of MoRF binding (P = 0.034);
MVP		0.97
MPC		1.2
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8
Varity_R		0.87
gMVP		0.97

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.93		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.93		Position offset: 0

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

Publications

LitVar

Other links and lift over

dbSNP: rs1975056596; hg19: chr17-4923374;