19-50908388-C-A

Variant names:

• chr19-50908388-C-A
• rs2090452538
• NM_004917.5:c.583G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_004917.5(KLK4):​c.583G>T​(p.Gly195*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,722 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: KLK4 NM_004917.5 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.19
• Publications: 0 publications found

Genes affected

KLK4 (HGNC:6365): (kallikrein related peptidase 4) Kallikreins are a subgroup of serine proteases having diverse physiological functions. Growing evidence suggests that many kallikreins are implicated in carcinogenesis and some have potential as novel cancer and other disease biomarkers. This gene is one of the fifteen kallikrein subfamily members located in a cluster on chromosome 19. In some tissues its expression is hormonally regulated. The expression pattern of a similar mouse protein in murine developing teeth supports a role for the protein in the degradation of enamel proteins. Several transcript variants encoding different proteins have been found for this gene. [provided by RefSeq, Dec 2014]

KLK4 Gene-Disease associations (from GenCC):

• amelogenesis imperfecta type 2A1

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• amelogenesis imperfecta type 2

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.238 CDS is truncated, and there are 3 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004917.5. 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
	KLK4	NM_004917.5	MANE Select	c.583G>T	p.Gly195*	stop_gained	Exon 5 of 6	NP_004908.4
	KLK4	NM_001302961.2		c.298G>T	p.Gly100*	stop_gained	Exon 4 of 5	NP_001289890.1
	KLK4	NR_126566.2		n.572G>T		non_coding_transcript_exon	Exon 4 of 5

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KLK4	ENST00000324041.6	TSL:1 MANE Select	c.583G>T	p.Gly195*	stop_gained	Exon 5 of 6	ENSP00000326159.1	A0A0C4DFQ5
	KLK4	ENST00000431178.2	TSL:1	c.328+191G>T		intron	N/A	ENSP00000399448.2	Q9Y5K2-2
	KLK4	ENST00000596876.1	TSL:1	n.585G>T		non_coding_transcript_exon	Exon 2 of 2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461722 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727176

African (AFR) AF: 0.00 AC: 0 AN: 33478

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: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53298

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5736

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1112012

Other (OTH) AF: 0.00 AC: 0 AN: 60384

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.25
CADD	Pathogenic	35
DANN	Benign	0.97
Eigen	Benign	-0.055
Eigen_PC	Benign	-0.43
FATHMM_MKL	Benign	0.029	N
PhyloP100		2.2
Vest4		0.56
GERP RS		1.2
Mutation Taster		=51/149	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs2090452538; hg19: chr19-51411644;