chr12-52651587-T-C

Variant names:

• chr12-52651587-T-C
• rs137852631
• NM_000423.3:c.556A>G

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP3_Strong PP5

The NM_000423.3(KRT2):​c.556A>G​(p.Asn186Asp) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N186Y) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: KRT2 NM_000423.3 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 6.27
• Publications: 7 publications found

Genes affected

KRT2 (HGNC:6439): (keratin 2) The protein encoded by this gene is a member of the keratin gene family. The type II cytokeratins consist of basic or neutral proteins which are arranged in pairs of heterotypic keratin chains coexpressed during differentiation of simple and stratified epithelial tissues. This type II cytokeratin is expressed largely in the upper spinous layer of epidermal keratinocytes and mutations in this gene have been associated with bullous congenital ichthyosiform erythroderma. The type II cytokeratins are clustered in a region of chromosome 12q12-q13. [provided by RefSeq, Jul 2008]

KRT2 Gene-Disease associations (from GenCC):

• superficial epidermolytic ichthyosis

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P, Orphanet, PanelApp Australia

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 5 uncertain in NM_000423.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-52651587-T-A is described in ClinVar as Pathogenic. ClinVar VariationId is 9313.Status of the report is no_assertion_criteria_provided, 0 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.972
• PP5: Variant 12-52651587-T-C is Pathogenic according to our data. Variant chr12-52651587-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 9315.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000423.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KRT2	NM_000423.3	MANE Select	c.556A>G	p.Asn186Asp	missense	Exon 1 of 9	NP_000414.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KRT2	ENST00000309680.4	TSL:1 MANE Select	c.556A>G	p.Asn186Asp	missense	Exon 1 of 9	ENSP00000310861.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Ichthyosis bullosa of Siemens Pathogenic:1

Jan 01, 2000

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.90	D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.81	T
M_CAP	Uncertain	0.15	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.5	H
PhyloP100		6.3
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-4.7	D
REVEL	Pathogenic	0.87
Sift	Uncertain	0.0060	D
Sift4G	Uncertain	0.0050	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.85		Loss of MoRF binding (P = 0.0443)
MVP		0.97
MPC		0.50
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.87
gMVP		0.97
Mutation Taster		=7/93	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: rs137852631; hg19: chr12-53045371;