1-200974857-G-GA

Variant names:

• chr1-200974857-G-GA
• NM_001252102.2:c.4670_4671insT

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_001252102.2(KIF21B):​c.4670_4671insT​(p.Met1559HisfsTer24) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: KIF21B NM_001252102.2 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.02

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KIF21B	NM_001252102.2	c.4670_4671insT	p.Met1559HisfsTer24	frameshift_variant	Exon 34 of 35	ENST00000461742.7	NP_001239031.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KIF21B	ENST00000461742.7	c.4670_4671insT	p.Met1559HisfsTer24	frameshift_variant	Exon 34 of 35	1	NM_001252102.2	ENSP00000433808.1
KIF21B	ENST00000422435.2	c.4670_4671insT	p.Met1559HisfsTer24	frameshift_variant	Exon 34 of 35	1		ENSP00000411831.2
KIF21B	ENST00000332129.6	c.4631_4632insT	p.Met1546HisfsTer24	frameshift_variant	Exon 33 of 34	1		ENSP00000328494.2
KIF21B	ENST00000360529.9	c.4631_4632insT	p.Met1546HisfsTer24	frameshift_variant	Exon 33 of 34	1		ENSP00000353724.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurodevelopmental disorder Uncertain:1

Jul 16, 2023

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0105 - The mechanism of disease for this gene is not clearly established. However functional evidence has demonstrated some missense variants 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) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0710 - Other NMD predicted variants comparable to the one identified in this case have inconclusive previous evidence for pathogenicity. p.(Lys573AsnfsTer58) has been classified as a VUS by a clinical laboratory in Clinvar, and p.(Asn988Serfs*4) has been observed as de novo in an individual with mild developmental delay and hypotonia in the literature (PMID: 32415109). (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) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.17		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-200943985;