1-200974903-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP2 PP5_Moderate

The NM_001252102.2(KIF21B):c.4625A>G(p.Asn1542Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,448 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 Likely pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: KIF21B NM_001252102.2 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.16

Genes affected

KIF21B (HGNC:29442): (kinesin family member 21B) This gene encodes a member of the kinesin superfamily. Kinesins are ATP-dependent microtubule-based motor proteins that are involved in the intracellular transport of membranous organelles. Single nucleotide polymorphisms in this gene are associated with inflammatory bowel disease and multiple sclerosis. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Nov 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, KIF21B
• PP5: Variant 1-200974903-T-C is Pathogenic according to our data. Variant chr1-200974903-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1699344.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KIF21B	NM_001252102.2	c.4625A>G	p.Asn1542Ser	missense_variant	34/35	ENST00000461742.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KIF21B	ENST00000461742.7	c.4625A>G	p.Asn1542Ser	missense_variant	34/35	1	NM_001252102.2	P3
KIF21B	ENST00000422435.2	c.4625A>G	p.Asn1542Ser	missense_variant	34/35	1
KIF21B	ENST00000332129.6	c.4586A>G	p.Asn1529Ser	missense_variant	33/34	1
KIF21B	ENST00000360529.9	c.4586A>G	p.Asn1529Ser	missense_variant	33/34	1		A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461448 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727064

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurodevelopmental disorder Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Jun 24, 2022

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Likely pathogenic. Following criteria are met: 0105 - The mechanism of disease for this gene is not clearly established. However functional evidence has demonstrated some missense variants to have a gain of function effect, a dominant negative effect, or both (PMID: 32415109). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from asparagine to serine. (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0600 - Variant is located in the annotated WD40 domain (PMID: 32415109). (I) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1203 - This variant has been shown to be de novo in the proband (parental status confirmed, by trio analysis). (SP) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.097
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.56
Cadd	Uncertain	25
Dann	Uncertain	1.0
Eigen	Uncertain	0.24
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D;D;D;D
M_CAP	Benign	0.011	T
MetaRNN	Benign	0.35	T;T;T;T
MetaSVM	Benign	-1.1	T
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Benign	0.43	T
PROVEAN	Uncertain	-3.2	D;D;D;D
REVEL	Benign	0.20
Sift	Uncertain	0.023	D;D;D;D
Sift4G	Benign	0.12	T;T;T;T
Polyphen		0.72	P;.;.;P
Vest4		0.56
MutPred		0.50		.;Gain of loop (P = 0.1069);.;Gain of loop (P = 0.1069);
MVP		0.38
MPC		0.41
ClinPred		0.97	D
GERP RS		4.7
Varity_R		0.25
gMVP		0.11

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.24		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.24		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs893498810; hg19: chr1-200944031;