12-25206111-G-GAA

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BS1_Supporting BS2

The NM_004985.5(KRAS):c.*3683_*3684insTT variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000208 in 206,860 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00019 (0 hom., cov: 31)
  • Exomes 𝑓: 0.00024 (0 hom.)
• Consequence: KRAS NM_004985.5 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 0.614

Genes affected

KRAS (HGNC:6407): (KRAS proto-oncogene, GTPase) This gene, a Kirsten ras oncogene homolog from the mammalian ras gene family, encodes a protein that is a member of the small GTPase superfamily. A single amino acid substitution is responsible for an activating mutation. The transforming protein that results is implicated in various malignancies, including lung adenocarcinoma, mucinous adenoma, ductal carcinoma of the pancreas and colorectal carcinoma. Alternative splicing leads to variants encoding two isoforms that differ in the C-terminal region. [provided by RefSeq, Jul 2008]

ETFRF1 (HGNC:27052): (electron transfer flavoprotein regulatory factor 1) Involved in respiratory electron transport chain. Located in mitochondrion. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_benign. Variant got -5 ACMG points.

• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000195 (29/148822) while in subpopulation AFR AF= 0.000662 (27/40790). AF 95% confidence interval is 0.000467. There are 0 homozygotes in gnomad4. There are 11 alleles in male gnomad4 subpopulation. Median coverage is 31. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High AC in GnomAd at 29 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KRAS	NM_004985.5	c.*3683_*3684insTT		3_prime_UTR_variant	5/5	ENST00000311936.8
KRAS	NM_033360.4	c.*3804_*3805insTT		3_prime_UTR_variant	6/6	ENST00000256078.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KRAS	ENST00000256078.10	c.*3804_*3805insTT		3_prime_UTR_variant	6/6	1	NM_033360.4	A1
KRAS	ENST00000311936.8	c.*3683_*3684insTT		3_prime_UTR_variant	5/5	1	NM_004985.5	P4

Frequencies

GnomAD3 genomes AF: 0.000195 AC: 29 AN: 148716 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.000664

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000667

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000212

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000241 AC: 14 AN: 58038 Hom.: 0 Cov.: 0 AF XY: 0.000261 AC XY: 7 AN XY: 26844

Gnomad4 AFR exome AF: 0.00382

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: 0.0000279

Gnomad4 OTH exome AF: 0.000416

GnomAD4 genome AF: 0.000195 AC: 29 AN: 148822 Hom.: 0 Cov.: 31 AF XY: 0.000152 AC XY: 11 AN XY: 72494

Gnomad4 AFR AF: 0.000662

Gnomad4 AMR AF: 0.0000666

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000213

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Cardio-facio-cutaneous syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Noonan syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs142323886; hg19: chr12-25359045;