12-52447359-A-G

Variant names:

• chr12-52447359-A-G
• rs749628792
• NM_005555.4:c.1526T>C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_005555.4(KRT6B):​c.1526T>C​(p.Leu509Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,674 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: KRT6B NM_005555.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.43

Genes affected

KRT6B (HGNC:6444): (keratin 6B) 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. Mutations in these genes have been associated with pachyonychia congenita. The type II cytokeratins are clustered in a region of chromosome 12q12-q13. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.18814632).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KRT6B	NM_005555.4	c.1526T>C	p.Leu509Pro	missense_variant	Exon 9 of 9	ENST00000252252.4	NP_005546.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KRT6B	ENST00000252252.4	c.1526T>C	p.Leu509Pro	missense_variant	Exon 9 of 9	1	NM_005555.4	ENSP00000252252.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251182 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135766

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461674 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727134

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000348

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Sep 06, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.25
BayesDel_addAF	Benign	-0.034	T
BayesDel_noAF	Benign	-0.19
CADD	Benign	21
DANN	Benign	0.89
DEOGEN2	Uncertain	0.50	D
Eigen	Benign	-0.67
Eigen_PC	Benign	-0.72
FATHMM_MKL	Benign	0.32	N
LIST_S2	Benign	0.011	T
M_CAP	Benign	0.069	D
MetaRNN	Benign	0.19	T
MetaSVM	Uncertain	-0.25	T
MutationAssessor	Uncertain	2.7	M
PrimateAI	Benign	0.37	T
PROVEAN	Uncertain	-3.6	D
REVEL	Benign	0.26
Sift	Benign	0.16	T
Sift4G	Benign	0.10	T
Polyphen		0.0020	B
Vest4		0.27
MutPred		0.34		Gain of catalytic residue at S513 (P = 0);
MVP		0.78
MPC		0.28
ClinPred		0.19	T
GERP RS		2.1
Varity_R		0.36
gMVP		0.61

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: rs749628792; hg19: chr12-52841143;