12-52288038-A-G

Variant names:

• chr12-52288038-A-G
• rs138597671
• NM_002281.4:c.846T>C

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Strong BP7

The NM_002281.4(KRT81):​c.846T>C​(p.Tyr282Tyr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000161 in 1,614,060 control chromosomes in the GnomAD database, with no homozygous occurrence. There is a variant allele frequency bias in the population database for this variant (GnomAdExome4), which may indicate mosaicism or somatic mutations in the reference population data. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000016 (0 hom.)
• Consequence: KRT81 NM_002281.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.964
• Publications: 5 publications found

Genes affected

KRT81 (HGNC:6458): (keratin 81) The protein encoded by this gene is a member of the keratin gene family. As a type II hair keratin, it is a basic protein which heterodimerizes with type I keratins to form hair and nails. The type II hair keratins are clustered in a region of chromosome 12q13 and are grouped into two distinct subfamilies based on structure similarity. One subfamily, consisting of KRTHB1, KRTHB3, and KRTHB6, is highly related. The other less-related subfamily includes KRTHB2, KRTHB4, and KRTHB5. All hair keratins are expressed in the hair follicle; this hair keratin, as well as KRTHB3 and KRTHB6, is found primarily in the hair cortex. Mutations in this gene and KRTHB6 have been observed in patients with a rare dominant hair disease, monilethrix. Some human genome assemblies (example T2T-CHM13) have a non-coding version of the gene due to the presence of a SNP that introduces a premature stop codon after codon 281. [provided by RefSeq, Jan 2024]

KRT86 (HGNC:6463): (keratin 86) This gene encodes a type II keratin protein, which heterodimerizes with type I keratins to form hair and nails. This gene is present in a cluster of related genes and pseudogenes on chromosome 12. Mutations in this gene have been observed in patients with the hair disease monilethrix. [provided by RefSeq, Feb 2016]

KRT86 Gene-Disease associations (from GenCC):

• monilethrix

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Orphanet
• monilethrix-1

  Inheritance: AD Classification: MODERATE Submitted by: G2P

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.9).
• BP7: Synonymous conserved (PhyloP=-0.964 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002281.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KRT81	NM_002281.4	MANE Select	c.846T>C	p.Tyr282Tyr	synonymous	Exon 5 of 9	NP_002272.2	Q14533
	KRT86	NM_001320198.2	MANE Select	c.-5+12092A>G		intron	N/A	NP_001307127.1	O43790

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KRT81	ENST00000327741.9	TSL:1 MANE Select	c.846T>C	p.Tyr282Tyr	synonymous	Exon 5 of 9	ENSP00000369349.4	Q14533
	KRT86	ENST00000423955.7	TSL:2 MANE Select	c.-5+12092A>G		intron	N/A	ENSP00000444533.1	O43790
	KRT86	ENST00000958042.1		c.-5+9354A>G		intron	N/A	ENSP00000628101.1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152188 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000795 AC: 2 AN: 251476 AF XY: 0.00000736

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000164 AC: 24 AN: 1461872 Hom.: 0 Cov.: 85 AF XY: 0.0000165 AC XY: 12 AN XY: 727228

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

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: 0.000197 AC: 17 AN: 86244

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000540 AC: 6 AN: 1112008

Other (OTH) AF: 0.0000166 AC: 1 AN: 60392

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152188 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74332

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000241 AC: 1 AN: 41448

American (AMR) AF: 0.00 AC: 0 AN: 15280

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5200

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2090

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.90
CADD	Benign	0.068
DANN	Benign	0.32
PhyloP100		-0.96

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

Other links and lift over

dbSNP: rs138597671; hg19: chr12-52681822; COSMIC: COSV59811000;