2-240740319-C-T

Variant names:

• chr2-240740319-C-T
• rs376759734
• NM_001244008.2:c.3795G>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001244008.2(KIF1A):​c.3795G>A​(p.Met1265Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,408 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M1265L) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: KIF1A NM_001244008.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.776
• Publications: 0 publications found

Genes affected

KIF1A (HGNC:888): (kinesin family member 1A) The protein encoded by this gene is a member of the kinesin family and functions as an anterograde motor protein that transports membranous organelles along axonal microtubules. Mutations at this locus have been associated with spastic paraplegia-30 and hereditary sensory neuropathy IIC. Alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Apr 2012]

KIF1A Gene-Disease associations (from GenCC):

• intellectual disability, autosomal dominant 9

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• syndromic intellectual disability

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• neuropathy, hereditary sensory, type 2C

  Inheritance: AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P
• hereditary spastic paraplegia 30

  Inheritance: AR, AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
• autosomal dominant non-syndromic intellectual disability

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• PEHO syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary sensory and autonomic neuropathy type 2

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.26510754).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KIF1A	NM_001244008.2	c.3795G>A	p.Met1265Ile	missense_variant	Exon 36 of 49	ENST00000498729.9	NP_001230937.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KIF1A	ENST00000498729.9	c.3795G>A	p.Met1265Ile	missense_variant	Exon 36 of 49	5	NM_001244008.2	ENSP00000438388.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000805 AC: 2 AN: 248376 AF XY: 0.00000742

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: 0.0000178

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461408 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 726962

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44708

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26112

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86234

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53302

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5734

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111788

Other (OTH) AF: 0.00 AC: 0 AN: 60354

GnomAD4 genome Cov.: 32

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000119 AC: 1

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Jul 19, 2023

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Neuropathy, hereditary sensory, type 2C;C5235139:Hereditary spastic paraplegia 30;C5393830:Intellectual disability, autosomal dominant 9 Uncertain:1

Jul 26, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has not been reported in the literature in individuals with KIF1A-related disease. 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 tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. 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. This variant is present in population databases (rs376759734, ExAC 0.003%). This sequence change replaces methionine with isoleucine at codon 1164 of the KIF1A protein (p.Met1164Ile). The methionine residue is moderately conserved and there is a small physicochemical difference between methionine and isoleucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.32
BayesDel_addAF	Benign	-0.082	T
BayesDel_noAF	Benign	-0.34
CADD	Benign	22
DANN	Benign	0.97
DEOGEN2	Benign	0.27	T;.;.;.;.;.;.;T;.;.;.;.;.;.
Eigen	Benign	-0.17
Eigen_PC	Benign	-0.10
FATHMM_MKL	Benign	0.63	D
LIST_S2	Uncertain	0.96	.;D;D;D;D;D;.;D;D;D;D;D;D;D
M_CAP	Benign	0.031	D
MetaRNN	Benign	0.27	T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.69	N;.;.;.;.;.;.;N;.;.;.;.;.;.
PhyloP100		0.78
PrimateAI	Uncertain	0.56	T
PROVEAN	Benign	-2.1	.;N;N;.;.;.;.;.;.;.;.;.;.;N
REVEL	Benign	0.078
Sift	Benign	0.11	.;T;T;.;.;.;.;.;.;.;.;.;.;T
Sift4G	Benign	0.49	.;T;T;.;.;.;.;.;.;.;.;.;.;.
Polyphen		0.019	B;.;.;.;.;.;.;B;.;.;.;.;.;B
Vest4		0.41, 0.42
MutPred		0.40		Gain of sheet (P = 0.1945);.;Gain of sheet (P = 0.1945);.;.;Gain of sheet (P = 0.1945);.;Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);.;.;.;.;.;
MVP		0.35
MPC		0.49
ClinPred		0.23	T
GERP RS		2.2
Varity_R		0.14
gMVP		0.34
Mutation Taster		=82/18	polymorphism

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: rs376759734; hg19: chr2-241679736;