rs886041209

Variant names:

• chr7-92241100-ACTTT-A
• rs886041209
• NM_194454.3:c.151_154delAAAG

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_194454.3(KRIT1):​c.151_154delAAAG​(p.Lys51PhefsTer13) variant causes a frameshift change. The variant allele was found at a frequency of 0.000000685 in 1,459,252 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: KRIT1 NM_194454.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 7.03

Genes affected

KRIT1 (HGNC:1573): (KRIT1 ankyrin repeat containing) This gene encodes a protein containing four ankyrin repeats, a band 4.1/ezrin/radixin/moesin (FERM) domain, and multiple NPXY sequences. The encoded protein is localized in the nucleus and cytoplasm. It binds to integrin cytoplasmic domain-associated protein-1 alpha (ICAP1alpha), and plays a critical role in beta1-integrin-mediated cell proliferation. It associates with junction proteins and RAS-related protein 1A (Rap1A), which requires the encoded protein for maintaining the integrity of endothelial junctions. It is also a microtubule-associated protein and may play a role in microtubule targeting. Mutations in this gene result in cerebral cavernous malformations. Multiple alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Sep 2009]

ENSG00000289027 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-92241100-ACTTT-A is Pathogenic according to our data. Variant chr7-92241100-ACTTT-A is described in ClinVar as [Pathogenic]. Clinvar id is 279827.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr7-92241100-ACTTT-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KRIT1	NM_194454.3	c.151_154delAAAG	p.Lys51PhefsTer13	frameshift_variant	Exon 5 of 19	ENST00000394505.7	NP_919436.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KRIT1	ENST00000394505.7	c.151_154delAAAG	p.Lys51PhefsTer13	frameshift_variant	Exon 5 of 19	1	NM_194454.3	ENSP00000378013.2
ENSG00000289027	ENST00000692281.1	c.151_154delAAAG	p.Lys51PhefsTer13	frameshift_variant	Exon 5 of 26			ENSP00000510568.1
ENSG00000285953	ENST00000458493.6	c.151_154delAAAG	p.Lys51PhefsTer13	frameshift_variant	Exon 4 of 20	4		ENSP00000396352.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459252 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 726240

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: 9.01e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000113

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Jul 27, 2016

PreventionGenetics, part of Exact Sciences

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 03, 2023

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 23595507, 12404106, 31254430, 30161288, 17043900) -

Inborn genetic diseases Pathogenic:1

Mar 26, 2024

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.151_154delAAAG (p.K51Ffs*13) alteration, located in exon 6 (coding exon 2) of the KRIT1 gene, consists of a deletion of 4 nucleotides from position 151 to 154, causing a translational frameshift with a predicted alternate stop codon after 13 amino acids. This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). This variant was reported in multiple individuals with features consistent with KRIT1-related cerebral cavernous malformations and cosegregates with disease in several families (Nardella, 2018; Riant, 2013; Cavé-Riant, 2002). Based on the available evidence, this alteration is classified as pathogenic. -

Cerebral cavernous malformation Pathogenic:1

Sep 16, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Lys51Phefs*13) in the KRIT1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in KRIT1 are known to be pathogenic (PMID: 10508515, 11222804, 12404106, 24689081). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with cerebral cavernous malformations (PMID: 12404106, 30161288). ClinVar contains an entry for this variant (Variation ID: 279827). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs886041209; hg19: chr7-91870414;