rs57758262

Variant names:

• chr17-41571505-C-A
• rs57758262
• NM_000226.4:c.488G>T

Your query was ambiguous. Multiple possible variants found:

• chr17-41571505-C-A
• chr17-41571505-C-G
• chr17-41571505-C-T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000226.4(KRT9):​c.488G>T​(p.Arg163Leu) 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 variant affecting the same amino acid position, but resulting in a different missense (i.e. R163P) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: KRT9 NM_000226.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 4.13
• Publications: 1 publications found

Genes affected

KRT9 (HGNC:6447): (keratin 9) This gene encodes the type I keratin 9, an intermediate filament chain expressed only in the terminally differentiated epidermis of palms and soles. Mutations in this gene cause epidermolytic palmoplantar keratoderma. [provided by RefSeq, Jul 2008]

KRT9 Gene-Disease associations (from GenCC):

• epidermolytic palmoplantar keratoderma, 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PM1: In a hotspot region, there are 12 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 10 uncertain in NM_000226.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-41571505-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 3001.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993
• PP5: Variant 17-41571505-C-A is Pathogenic according to our data. Variant chr17-41571505-C-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 3237488.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KRT9	NM_000226.4	c.488G>T	p.Arg163Leu	missense_variant	Exon 1 of 8	ENST00000246662.9	NP_000217.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KRT9	ENST00000246662.9	c.488G>T	p.Arg163Leu	missense_variant	Exon 1 of 8	1	NM_000226.4	ENSP00000246662.4
KRT9	ENST00000588431.1	c.-189-23G>T		intron_variant	Intron 1 of 8	1		ENSP00000467932.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Epidermolytic palmoplantar keratoderma, 1 Pathogenic:1

Jan 16, 2024

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Pathogenic:1

Jun 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 163 of the KRT9 protein (p.Arg163Leu). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with epidermolytic palmoplantar keratoderma (PMID: 27726289). It has also been observed to segregate with disease in related individuals. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt KRT9 protein function with a positive predictive value of 80%. This variant disrupts the p.Arg163 amino acid residue in KRT9. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 22262370). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.81
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.42
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D
Eigen	Uncertain	0.25
Eigen_PC	Benign	0.033
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.44	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.83	D
MutationAssessor	Pathogenic	3.5	H
PhyloP100		4.1
PrimateAI	Benign	0.31	T
PROVEAN	Pathogenic	-6.6	D
REVEL	Pathogenic	0.82
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0030	D
Polyphen		0.99	D
Vest4		0.87
MutPred		0.90		Loss of disorder (P = 0.0682);
MVP		0.94
MPC		0.46
ClinPred		0.99	D
GERP RS		2.6
Varity_R		0.83
gMVP		0.95
Mutation Taster		=18/82	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.23		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.23		Position offset: -23

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

Other links and lift over

dbSNP: rs57758262; hg19: chr17-39727757;