NM_001395891.1:c.196-584C>T

Variant names:

• chr2-121530909-G-A
• rs374299350
• NM_001395891.1:c.196-584C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 8P and 2B. PP5_Very_Strong BP4 BS2_Supporting

The NM_001395891.1(CLASP1):​c.196-584C>T variant causes a intron change. The variant allele was found at a frequency of 0.0000601 in 699,036 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: 𝑓 0.000053 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000062 (0 hom.)
• Consequence: CLASP1 NM_001395891.1 intron
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 3.66
• Publications: 2 publications found

Genes affected

CLASP1 (HGNC:17088): (cytoplasmic linker associated protein 1) CLASPs, such as CLASP1, are nonmotor microtubule-associated proteins that interact with CLIPs (e.g., CLIP170; MIM 179838). CLASP1 is involved in the regulation of microtubule dynamics at the kinetochore and throughout the spindle (Maiato et al., 2003 [PubMed 12837247]).[supplied by OMIM, Mar 2008]

RNU4ATAC (HGNC:34016): (RNA, U4atac small nuclear) The small nuclear RNA (snRNA) encoded by this gene is part of the U12-dependent minor spliceosome complex. In addition to the encoded RNA, this ribonucleoprotein complex consists of U11, U12, U5, and U6atac snRNAs. The U12-dependent spliceosome acts on approximately 700 specific introns in the human genome. Defects in this gene are a cause of microcephalic osteodysplastic primordial dwarfism type 1 (MOPD). [provided by RefSeq, Jul 2011]

CLASP1-AS1 (HGNC:55328): (CLASP1 antisense RNA 1)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PP5: Variant 2-121530909-G-A is Pathogenic according to our data. Variant chr2-121530909-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 30180.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.3). . Strength limited to SUPPORTING due to the PP5.
• BS2: High AC in GnomAd4 at 8 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CLASP1	NM_001395891.1	c.196-584C>T		intron_variant	Intron 2 of 40	ENST00000696935.1	NP_001382820.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CLASP1	ENST00000696935.1	c.196-584C>T		intron_variant	Intron 2 of 40		NM_001395891.1	ENSP00000512981.1

Frequencies

GnomAD3 genomes AF: 0.0000526 AC: 8 AN: 152180 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000965

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: 0.000189

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.000478

GnomAD2 exomes AF: 0.0000613 AC: 8 AN: 130408 AF XY: 0.0000562

Gnomad AFR exome AF: 0.000164

Gnomad AMR exome AF: 0.0000411

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000192

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000604

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000622 AC: 34 AN: 546738 Hom.: 0 Cov.: 0 AF XY: 0.0000575 AC XY: 17 AN XY: 295832

African (AFR) AF: 0.0000636 AC: 1 AN: 15718

American (AMR) AF: 0.0000288 AC: 1 AN: 34676

Ashkenazi Jewish (ASJ) AF: 0.0000500 AC: 1 AN: 19998

East Asian (EAS) AF: 0.000187 AC: 6 AN: 32064

South Asian (SAS) AF: 0.0000639 AC: 4 AN: 62640

European-Finnish (FIN) AF: 0.0000301 AC: 1 AN: 33180

Middle Eastern (MID) AF: 0.000410 AC: 1 AN: 2440

European-Non Finnish (NFE) AF: 0.0000539 AC: 17 AN: 315658

Other (OTH) AF: 0.0000659 AC: 2 AN: 30364

GnomAD4 genome AF: 0.0000525 AC: 8 AN: 152298 Hom.: 0 Cov.: 32 AF XY: 0.0000537 AC XY: 4 AN XY: 74470

African (AFR) AF: 0.0000962 AC: 4 AN: 41568

American (AMR) AF: 0.00 AC: 0 AN: 15304

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.000189 AC: 2 AN: 10600

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68032

Other (OTH) AF: 0.000473 AC: 1 AN: 2112

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000945

Asia WGS AF: 0.000577 AC: 2 AN: 3478

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Osteodysplastic primordial dwarfism, type 1 Pathogenic:2

Jan 01, 2018

Diagnostics Division, CENTRE FOR DNA FINGERPRINTING AND DIAGNOSTICS

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

The same individual also harbours another variant g.122288495C>T in the same gene along with this variant as compound heterozygote -

Apr 08, 2011

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

not provided Pathogenic:1

Jan 27, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant occurs in the RNU4ATAC gene, which encodes an RNA molecule that does not result in a protein product. This variant is present in population databases (rs374299350, gnomAD 0.01%). This variant has been observed in individual(s) with clinical features of microcephalic osteodysplastic primordial dwarfism type 1 (PMID: 21474760). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 30180). Functional studies have shown that this variant disrupts ncRNA function (PMID: 21474760). This variant is located within the 5' stem-loop region of the RNU4ATAC RNA, which includes the 15.5K binding site and is important for spliceosome assembly (PMID: 32628740). A significant number of disease-associated RNU4ATAC variants are found in this region (PMID: 32628740, 30368667). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.30
CADD	Benign	17
DANN	Benign	0.93
PhyloP100		3.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Mutation Taster		=6/94	disease causing (ClinVar)

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: rs374299350; hg19: chr2-122288485;