rs60723330

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_005557.4(KRT16):​c.374A>G​(p.Asn125Ser) 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N125G) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

KRT16
NM_005557.4 missense

Scores

10
7
2

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:6O:1

Conservation

PhyloP100: 6.18

Publications

20 publications found
Variant links:
Genes affected
KRT16 (HGNC:6423): (keratin 16) The protein encoded by this gene is a member of the keratin gene family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. Most of the type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains and are clustered in a region of chromosome 17q12-q21. This keratin has been coexpressed with keratin 14 in a number of epithelial tissues, including esophagus, tongue, and hair follicles. Mutations in this gene are associated with type 1 pachyonychia congenita, non-epidermolytic palmoplantar keratoderma and unilateral palmoplantar verrucous nevus. [provided by RefSeq, Jul 2008]
KRT16 Gene-Disease associations (from GenCC):
  • pachyonychia congenita 1
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
  • palmoplantar keratoderma, nonepidermolytic, focal 1
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Genomics England PanelApp
  • isolated focal non-epidermolytic palmoplantar keratoderma
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • pachyonychia congenita
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PM1
In a hotspot region, there are 13 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_005557.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr17-41612315-TT-CC is described in ClinVar as Pathogenic. ClinVar VariationId is 156024.Status of the report is no_assertion_criteria_provided, 0 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.992
PP5
Variant 17-41612315-T-C is Pathogenic according to our data. Variant chr17-41612315-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 14602.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
KRT16NM_005557.4 linkc.374A>G p.Asn125Ser missense_variant Exon 1 of 8 ENST00000301653.9 NP_005548.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KRT16ENST00000301653.9 linkc.374A>G p.Asn125Ser missense_variant Exon 1 of 8 1 NM_005557.4 ENSP00000301653.3
KRT16ENST00000588319.1 linkn.451A>G non_coding_transcript_exon_variant Exon 1 of 1 6
KRT16ENST00000593067.1 linkc.-312-29A>G intron_variant Intron 1 of 6 3 ENSP00000467124.1
KRT16ENST00000590990.1 linkc.*228A>G downstream_gene_variant 4 ENSP00000467105.1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
Data not reliable, filtered out with message: AS_VQSR
AF:
6.84e-7
AC:
1
AN:
1461888
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:6Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:3Other:1
Nov 14, 2024
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Immunostaining of tooth enamel from a PC patient with the N125S variant showed abnormal K16 protein aggregation and atypical cracks within the inner enamel, and in vitro expression demonstrated altered keratin intermediate filament assembly and intracellular clumping (PMID: 30009827); Multiple pathogenic missense variants have been reported in this codon (N125G and N125D) and in nearby residues (Q122R, Q122P, L124H, L124P, L124R, R127G, R127S, R127C, R127P, R127H, L128Q, L128P) in association with KRT16-related disorders in the Human Gene Mutation Database (HGMD); Located in the highly conserved helix initiation motif of the alpha-helical rod domain, which is intolerant to change; variants in this motif interfere with proper keratin intermediate filament assembly and function, resulting in skin fragility and/or hyperkeratosis (PMID: 21176769); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 24491404, 8595410, 28794556, 30859684, 31021398, 16250206, 21160496, 31823354, 21326300, 17719747, 38191074, 30009827, 21176769) -

Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 125 of the KRT16 protein (p.Asn125Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with pachyonychia congenita (PMID: 8595410, 24491404, 31823354; internal data). It has also been observed to segregate with disease in related individuals. This variant is also known as N8S. ClinVar contains an entry for this variant (Variation ID: 14602). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on KRT16 protein function. This variant disrupts the p.Asn125 amino acid residue in KRT16. Other variant(s) that disrupt this residue have been observed in individuals with KRT16-related conditions (PMID: 22668561), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -

-
Epithelial Biology; Institute of Medical Biology, Singapore
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Oct 23, 2020
Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Pachyonychia congenita 1;C4552049:Palmoplantar keratoderma, nonepidermolytic, focal 1 Pathogenic:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Pachyonychia congenita 1 Pathogenic:1
Oct 01, 2005
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Palmoplantar keratoderma, nonepidermolytic, focal 1 Pathogenic:1
Oct 01, 2005
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Pathogenic
0.22
D
BayesDel_noAF
Uncertain
0.070
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.87
D
Eigen
Pathogenic
0.72
Eigen_PC
Uncertain
0.58
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.90
D
M_CAP
Uncertain
0.25
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
4.2
H
PhyloP100
6.2
PrimateAI
Benign
0.46
T
PROVEAN
Uncertain
-4.4
D
REVEL
Pathogenic
0.84
Sift
Uncertain
0.010
D
Sift4G
Pathogenic
0.0
D
Polyphen
0.99
D
Vest4
0.93
MutPred
0.99
Loss of stability (P = 0.0688);
MVP
0.89
MPC
0.83
ClinPred
1.0
D
GERP RS
3.4
PromoterAI
-0.041
Neutral
Varity_R
0.41
gMVP
1.0
Mutation Taster
=24/76
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

Publications

Other links and lift over

dbSNP: rs60723330; hg19: chr17-39768567; API