rs59429455

Positions:

• chr12-52679785-G-C
• chr12-52679785-G-T

Variant summary

Our verdict is Pathogenic. Variant got 20 ACMG points: 20P and 0B. PS1_Very_Strong PM1 PM2 PM5 PP3_Strong PP5_Moderate

The NM_006121.4(KRT1):​c.564C>G​(p.Asn188Lys) 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 Likely pathogenic (★). Another nucleotide change resulting in same amino acid change has been previously reported as Pathogenicin ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N188T) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: KRT1 NM_006121.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.00

Genes affected

KRT1 (HGNC:6412): (keratin 1) 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 specifically expressed in the spinous and granular layers of the epidermis with family member KRT10 and mutations in these genes 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]

ACMG classification

Verdict is Pathogenic. Variant got 20 ACMG points.

• PS1: Transcript NM_006121.4 (KRT1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar as 15914
• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_006121.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-52679786-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 66650.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.979
• PP5: Variant 12-52679785-G-C is Pathogenic according to our data. Variant chr12-52679785-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 997963.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KRT1	NM_006121.4	c.564C>G	p.Asn188Lys	missense_variant	1/9	ENST00000252244.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KRT1	ENST00000252244.3	c.564C>G	p.Asn188Lys	missense_variant	1/9	1	NM_006121.4	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Annular epidermolytic ichthyosis Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

KK Women’s and Children’s Hospital

Feb 28, 2021

Inherited from the mother who is a mosaic carrier and had systematized epidermolytic nevi with extensive, linear and Blaschkoid verrucous plaques and hyperkeratotic lesions of the trunk and limbs. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Uncertain	0.10
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	D
Eigen	Pathogenic	0.77
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.61	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Pathogenic	4.4	H
MutationTaster	Benign	0.98	D
PrimateAI	Uncertain	0.73	T
PROVEAN	Pathogenic	-5.3	D
REVEL	Pathogenic	0.73
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.83		Gain of methylation at N188 (P = 0.0197);
MVP		0.98
MPC		1.0
ClinPred		1.0	D
GERP RS		2.7
Varity_R		0.83
gMVP		0.98

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

Publications

LitVar

Other links and lift over

dbSNP: rs59429455; hg19: chr12-53073569;