NM_001365951.3:c.2120A>T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4BS2

The NM_001365951.3(KIF1B):​c.2120A>T​(p.Tyr707Phe) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000789 in 1,608,766 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 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000086 ( 0 hom. )

Consequence

KIF1B
NM_001365951.3 missense

Scores

2
12
5

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 8.94

Publications

1 publications found
Variant links:
Genes affected
KIF1B (HGNC:16636): (kinesin family member 1B) Predicted to enable microtubule binding activity and plus-end-directed microtubule motor activity. Predicted to be involved in chemical synaptic transmission; dense core granule cytoskeletal transport; and vesicle-mediated transport. Predicted to act upstream of or within mitochondrion transport along microtubule. Predicted to be located in cytoplasmic vesicle membrane and neuron projection. Predicted to be part of kinesin complex. Predicted to be active in several cellular components, including axon; dendrite; and microtubule. Implicated in Charcot-Marie-Tooth disease type 2A1; carcinoma (multiple); multiple sclerosis; neuroblastoma; and pheochromocytoma. Biomarker of hepatocellular carcinoma. [provided by Alliance of Genome Resources, Apr 2022]
KIF1B Gene-Disease associations (from GenCC):
  • pheochromocytoma
    Inheritance: AD Classification: MODERATE, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • Charcot-Marie-Tooth disease type 2A1
    Inheritance: AD Classification: SUPPORTIVE, LIMITED, NO_KNOWN Submitted by: Ambry Genetics, ClinGen, Orphanet, Labcorp Genetics (formerly Invitae)
  • hereditary pheochromocytoma-paraganglioma
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • neuroblastoma, susceptibility to, 1
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.32927436).
BS2
High AC in GnomAdExome4 at 126 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KIF1BNM_001365951.3 linkc.2120A>T p.Tyr707Phe missense_variant Exon 23 of 49 ENST00000676179.1 NP_001352880.1
KIF1BNM_001365952.1 linkc.2120A>T p.Tyr707Phe missense_variant Exon 23 of 49 NP_001352881.1
KIF1BNM_015074.3 linkc.1982A>T p.Tyr661Phe missense_variant Exon 21 of 47 NP_055889.2 O60333-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KIF1BENST00000676179.1 linkc.2120A>T p.Tyr707Phe missense_variant Exon 23 of 49 NM_001365951.3 ENSP00000502065.1 O60333-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152034
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000797
AC:
2
AN:
250980
AF XY:
0.0000147
show subpopulations
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:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000865
AC:
126
AN:
1456732
Hom.:
0
Cov.:
29
AF XY:
0.000101
AC XY:
73
AN XY:
725052
show subpopulations
African (AFR)
AF:
0.0000300
AC:
1
AN:
33362
American (AMR)
AF:
0.00
AC:
0
AN:
44682
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26100
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39654
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86122
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53320
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.000113
AC:
125
AN:
1107514
Other (OTH)
AF:
0.00
AC:
0
AN:
60214
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.455
Heterozygous variant carriers
0
6
12
19
25
31
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152034
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74264
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000242
AC:
1
AN:
41374
American (AMR)
AF:
0.00
AC:
0
AN:
15266
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10574
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2074
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000624
Hom.:
0
Bravo
AF:
0.00000378
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jun 03, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1982A>T (p.Y661F) alteration is located in exon 21 (coding exon 20) of the KIF1B gene. This alteration results from a A to T substitution at nucleotide position 1982, causing the tyrosine (Y) at amino acid position 661 to be replaced by a phenylalanine (F). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Charcot-Marie-Tooth disease type 2 Uncertain:1
Jul 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with phenylalanine, which is neutral and non-polar, at codon 661 of the KIF1B protein (p.Tyr661Phe). This variant is present in population databases (rs140536329, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with KIF1B-related conditions. ClinVar contains an entry for this variant (Variation ID: 476782). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt KIF1B protein function with a negative predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.42
BayesDel_addAF
Uncertain
0.092
D
BayesDel_noAF
Benign
-0.090
CADD
Uncertain
24
DANN
Uncertain
0.98
DEOGEN2
Uncertain
0.72
.;D;.;.;.
Eigen
Uncertain
0.44
Eigen_PC
Uncertain
0.55
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.96
D;D;D;D;D
M_CAP
Benign
0.036
D
MetaRNN
Benign
0.33
T;T;T;T;T
MetaSVM
Uncertain
-0.071
T
MutationAssessor
Uncertain
2.4
.;M;M;.;.
PhyloP100
8.9
PrimateAI
Pathogenic
0.82
D
PROVEAN
Uncertain
-3.1
D;D;D;.;.
REVEL
Uncertain
0.45
Sift
Uncertain
0.022
D;D;D;.;.
Sift4G
Benign
0.23
T;T;T;T;T
Polyphen
0.98
D;B;.;B;.
Vest4
0.57
MVP
0.73
MPC
1.0
ClinPred
0.94
D
GERP RS
5.6
Varity_R
0.48
gMVP
0.91
Mutation Taster
=77/23
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

Publications

Other links and lift over

dbSNP: rs140536329; hg19: chr1-10380105; API