12-52675216-T-C

Variant summary

Our verdict is Benign. Variant got -11 ACMG points: 0P and 11B. BP4_ModerateBP6BS1BS2

The NM_006121.4(KRT1):c.1912A>G(p.Thr638Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000106 in 1,613,844 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T638S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00011 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00011 ( 1 hom. )

Consequence

KRT1
NM_006121.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:2

Conservation

PhyloP100: 2.54

Variant links:

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]

KRT1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -11 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.08224276).

BP6

Variant 12-52675216-T-C is Benign according to our data. Variant chr12-52675216-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 309636.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=1, Likely_benign=1, Benign=1}. Variant chr12-52675216-T-C is described in Lovd as [Likely_benign].

BS1

Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.000105 (16/152294) while in subpopulation AMR AF= 0.000261 (4/15298). AF 95% confidence interval is 0.0000887. There are 0 homozygotes in gnomad4. There are 8 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.

BS2

High AC in GnomAd at 16 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KRT1	NM_006121.4 linkuse as main transcript	c.1912A>G	p.Thr638Ala	missense_variant	9/9	ENST00000252244.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KRT1	ENST00000252244.3 linkuse as main transcript	c.1912A>G	p.Thr638Ala	missense_variant	9/9	1	NM_006121.4	P1

Frequencies

GnomAD3 genomes

AF:

0.000105

AC:

AN:

152176

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000262

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00316

Gnomad NFE

AF:

0.000118

Gnomad OTH

AF:

0.000958

GnomAD3 exomes

AF:

0.000124

AC:

AN:

250926

Hom.:

AF XY:

0.000147

AC XY:

AN XY:

135736

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000260

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000185

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.000106

AC:

155

AN:

1461550

Hom.:

Cov.:

AF XY:

0.0000922

AC XY:

AN XY:

727066

show subpopulations

Gnomad4 AFR exome

AF:

0.0000598

Gnomad4 AMR exome

AF:

0.000358

Gnomad4 ASJ exome

AF:

0.0000383

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000103

Gnomad4 OTH exome

AF:

0.000199

GnomAD4 genome

AF:

0.000105

AC:

AN:

152294

Hom.:

Cov.:

AF XY:

0.000107

AC XY:

AN XY:

74476

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.000261

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000118

Gnomad4 OTH

AF:

0.000948

Alfa

AF:

0.000141

Hom.:

Bravo

AF:

0.000121

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000233

AC:

ExAC

AF:

0.000107

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.000296

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 12, 2021

The c.1912A>G (p.T638A) alteration is located in exon 9 (coding exon 9) of the KRT1 gene. This alteration results from a A to G substitution at nucleotide position 1912, causing the threonine (T) at amino acid position 638 to be replaced by an alanine (A). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Bullous ichthyosiform erythroderma

Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Diffuse nonepidermolytic palmoplantar keratoderma

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.086

BayesDel_addAF

Benign

-0.28

BayesDel_noAF

Benign

-0.34

Cadd

Benign

Dann

Benign

0.58

DEOGEN2

Benign

0.081

Eigen

Benign

-0.57

Eigen_PC

Benign

-0.48

FATHMM_MKL

Benign

0.70

LIST_S2

Benign

0.33

M_CAP

Benign

0.064

MetaRNN

Benign

0.082

MetaSVM

Benign

-0.66

MutationAssessor

Benign

2.0

MutationTaster

Benign

1.0

PrimateAI

Benign

0.38

PROVEAN

Benign

-1.1

REVEL

Benign

0.24

Sift

Pathogenic

0.0

Sift4G

Uncertain

0.0070

Polyphen

0.075

Vest4

0.13

MVP

0.36

MPC

0.26

ClinPred

0.093

GERP RS

3.8

Varity_R

0.30

gMVP

0.60

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over