Genetic Information

Gene & Transcript Details

Gene
KRAS
Transcript
NM_033360.4 MANE Select
Total Exons
Reference Sequence
NC_000012.11
Alternative Transcripts
IDStatusDetails
NM_033360.2 Alternative 5436 nt | 182–751
NM_033360.4 Alternative 5430 nt | 191–760
NM_033360.3 Alternative 5889 nt | 193–762

Variant Details

HGVS Notation
NM_033360.4:c.451-22G>T
Protein Change
?
Location
Exon 4 (Exon 4 of )
4
5'Exon Structure3'
Functional Consequence
Loss of Function
Alternate Identifiers

Clinical & Population Data

Population Frequency

gnomAD
Global Frequency
0.000398 in 100,000
Extremely Rare
ACMG Criteria Applied PM2
This variant is absent or extremely rare in population databases (PM2 criteria applies).

ClinVar

Open
Classification
Unknown
0 publications
Clinical Statement

""

COSMIC Somatic Evidence

Open
COSMIC ID
Recurrence
0 occurrences
PM1 Criteria
Not Applied
COSMIC Database Preview
COSMIC Preview
Accessing full COSMIC database details requires institutional login or subscription.

Functional Impact & Domains

Functional Domain

Hotspot Status
Not a hotspot
Domain Summary
This variant is not located in a mutational hotspot or critical domain.
Related Variants in This Domain
No evidence of other pathogenic variants at this position in gene KRAS.

Functional Studies & Therapeutic Relevance

Functional Summary

The KRAS 451-22g>T variant has not been functionally characterized.

Database Previews
OncoKB
OncoKB Preview
JAX-CKB
JAX-CKB Preview

Click on previews to view full database entries. External databases may require institutional access.

Computational Analysis

Pathogenicity Predictions

SpliceAI
Predictor Consensus
Mixed/VUS
PP3 Applied
No
REVEL Score
0.0
Threshold: ≥0.75 = PP3 applied

SpliceAI Scores

Window: ±500bp
Effect Type Score Position
- Acceptor Loss (AL) 0.01 8 bp
- Donor Loss (DL) 0.0 -48 bp
+ Acceptor Gain (AG) 0.06 -22 bp
+ Donor Gain (DG) 0.1 -145 bp
High impact (≥0.5) Medium impact (0.2-0.49) Low impact (<0.2)

VCEP Guidelines

Applied ACMG/AMP Criteria (VCEP Specific)

Filter Criteria:
PVS1

PVS1 (Not Applied)

According to standard ACMG guidelines, PVS1 pertains to null variants in a gene where loss of function is a known mechanism. The evidence shows NM_033360.4:c.451-22G>T is an intronic non-canonical splice region variant and KRAS disease mechanism is gain-of-function. Therefore, this criterion is not applied.

PS1

PS1 (Not Applied)

According to VCEP guidelines, PS1 requires the same amino acid change as a known pathogenic variant. The evidence shows this variant is intronic (no amino acid change). Therefore, this criterion is not applied.

PS2

PS2 (Not Applied)

According to VCEP guidelines, PS2 requires de novo occurrence with confirmed maternity and paternity. Parental data are not available. Therefore, this criterion is not applied.

PS3

PS3 (Not Applied)

According to VCEP guidelines, PS3 requires well-validated functional studies demonstrating a deleterious effect. No functional assays for this variant are available. Therefore, this criterion is not applied.

PS4

PS4 (Not Applied)

According to VCEP guidelines, PS4 requires case-level or case-control data showing increased prevalence in affected individuals. No such data are available. Therefore, this criterion is not applied.

PM1

PM1 (Not Applied)

According to VCEP guidelines, PM1 applies to missense variants in defined functional domains. This is an intronic variant outside canonical splice sites. Therefore, this criterion is not applied.

PM2

PM2 (Not Applied)

According to VCEP guidelines, PM2 (Supporting) requires absence from controls in gnomAD. The variant is present in gnomAD at MAF=0.000398%. Therefore, this criterion is not applied.

PM3

PM3 (Not Applied)

According to standard ACMG guidelines, PM3 applies to detected in trans for recessive disorders. Not applicable for this dominant gain-of-function gene. Therefore, this criterion is not applied.

PM4

PM4 (Not Applied)

According to VCEP guidelines, PM4 applies to protein length changes like in-frame indels. This is intronic with no coding effect. Therefore, this criterion is not applied.

PM5

PM5 (Not Applied)

According to VCEP guidelines, PM5 applies to novel missense changes at a codon with known pathogenic missense variants. This is intronic. Therefore, this criterion is not applied.

PM6

PM6 (Not Applied)

According to VCEP guidelines, PM6 requires assumed de novo occurrence without confirmation. No parental data are available. Therefore, this criterion is not applied.

PP1

PP1 (Not Applied)

According to VCEP guidelines, PP1 requires segregation data in affected family members. No segregation data are available. Therefore, this criterion is not applied.

PP2

PP2 (Not Applied)

According to standard ACMG guidelines, PP2 applies to missense variants in a gene with low rate of benign missense. This is intronic. Therefore, this criterion is not applied.

PP3

PP3 (Not Applied)

According to VCEP guidelines, PP3 (Supporting) requires REVEL ≥0.7 for missense or splicing predictions matching mechanism. SpliceAI predicts no significant impact (score ≤0.10). Therefore, this criterion is not applied.

PP4

PP4 (Not Applied)

According to standard ACMG guidelines, PP4 requires a specific phenotype highly specific for this gene. No phenotype data are provided. Therefore, this criterion is not applied.

PP5

PP5 (Not Applied)

According to standard ACMG guidelines, PP5 requires a reputable source classifying the variant as pathogenic. The variant is not in ClinVar. Therefore, this criterion is not applied.

BA1

BA1 (Not Applied)

According to VCEP guidelines, BA1 requires allele frequency ≥0.05% in gnomAD. The variant frequency is 0.000398%. Therefore, this criterion is not applied.

BS1

BS1 (Not Applied)

According to VCEP guidelines, BS1 requires allele frequency ≥0.025% in gnomAD. The variant frequency is 0.000398%. Therefore, this criterion is not applied.

BS2

BS2 (Not Applied)

According to standard ACMG guidelines, BS2 requires observation in healthy adults for fully penetrant disorders. No such data are available. Therefore, this criterion is not applied.

BS3

BS3 (Not Applied)

According to standard ACMG guidelines, BS3 requires well-established functional studies showing no deleterious effect. No functional data are available. Therefore, this criterion is not applied.

BS4

BS4 (Not Applied)

According to VCEP guidelines, BS4 requires lack of segregation with disease. No segregation data are available. Therefore, this criterion is not applied.

BP1

BP1 (Not Applied)

According to VCEP guidelines, BP1 applies to truncating variants in a gain-of-function gene. This is intronic, not truncating. Therefore, this criterion is not applied.

BP2

BP2 (Not Applied)

According to standard ACMG guidelines, BP2 requires observation in cis with a pathogenic variant. No such data are available. Therefore, this criterion is not applied.

BP3

BP3 (Not Applied)

According to standard ACMG guidelines, BP3 applies to in-frame indels in repetitive regions. This is intronic. Therefore, this criterion is not applied.

BP4

BP4 (Supporting)

According to standard ACMG guidelines, BP4 (Supporting) applies when multiple computational lines suggest no impact. SpliceAI score 0.10 and CADD 3.85 indicate no impact on splicing or function. Therefore, this criterion is applied at Supporting strength.

BP5

BP5 (Not Applied)

According to standard ACMG guidelines, BP5 requires an alternative benign explanation in a patient. No such data are available. Therefore, this criterion is not applied.

BP6

BP6 (Not Applied)

According to standard ACMG guidelines, BP6 requires a reputable source classifying the variant as benign without evidence. The variant is not in any database. Therefore, this criterion is not applied.

BP7

BP7 (Supporting)

According to VCEP guidelines, BP7 (Supporting) applies to intronic variants outside canonical splice sites with splicing predictions showing no impact. SpliceAI prediction is minimal. Therefore, this criterion is applied at Supporting strength.