12-52488079-T-C

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BS1 BS2

The NM_005554.4(KRT6A):c.1449A>G(p.Gln483=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00012 in 1,613,988 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00012 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00012 (1 hom.)
• Consequence: KRT6A NM_005554.4 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: -1.69

Genes affected

KRT6A (HGNC:6443): (keratin 6A) 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. As many as six of this type II cytokeratin (KRT6) have been identified; the multiplicity of the genes is attributed to successive gene duplication events. The genes are expressed with family members KRT16 and/or KRT17 in the filiform papillae of the tongue, the stratified epithelial lining of oral mucosa and esophagus, the outer root sheath of hair follicles, and the glandular epithelia. This KRT6 gene in particular encodes the most abundant isoform. Mutations in these genes have been associated with pachyonychia congenita. In addition, peptides from the C-terminal region of the protein have antimicrobial activity against bacterial pathogens. The type II cytokeratins are clustered in a region of chromosome 12q12-q13. [provided by RefSeq, Oct 2014]

ACMG classification

Verdict is Benign. Variant got -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP6: Variant 12-52488079-T-C is Benign according to our data. Variant chr12-52488079-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 1012820.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-1.69 with no splicing effect.
• BS1: Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.000118 (18/152256) while in subpopulation AMR AF= 0.000261 (4/15302). AF 95% confidence interval is 0.0000887. There are 0 homozygotes in gnomad4. There are 12 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High AC in GnomAd at 18 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KRT6A	NM_005554.4	c.1449A>G	p.Gln483=	synonymous_variant	8/9	ENST00000330722.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KRT6A	ENST00000330722.7	c.1449A>G	p.Gln483=	synonymous_variant	8/9	1	NM_005554.4	P1

Frequencies

GnomAD3 genomes AF: 0.000118 AC: 18 AN: 152138 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000483

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: 0.00

Gnomad NFE AF: 0.000118

Gnomad OTH AF: 0.00191

GnomAD3 exomes AF: 0.000167 AC: 42 AN: 251346 Hom.: 0 AF XY: 0.000199 AC XY: 27 AN XY: 135844

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000434

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000229

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000120 AC: 175 AN: 1461732 Hom.: 1 Cov.: 35 AF XY: 0.000122 AC XY: 89 AN XY: 727182

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000470

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.000130

Gnomad4 OTH exome AF: 0.000116

GnomAD4 genome AF: 0.000118 AC: 18 AN: 152256 Hom.: 0 Cov.: 32 AF XY: 0.000161 AC XY: 12 AN XY: 74454

Gnomad4 AFR AF: 0.0000481

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: 0.00189

Alfa AF: 0.000142 Hom.: 0

Bravo AF: 0.000166

EpiCase AF: 0.000273

EpiControl AF: 0.000237

ClinVar

Significance: Likely benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Invitae	Oct 28, 2022	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Dec 01, 2020	- -

KRT6A-related disorder Benign:1

Likely benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Jun 25, 2019

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
Cadd	Benign	4.4
Dann	Benign	0.59

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs372218481; hg19: chr12-52881863;