rs1555679863

Variant names:

• chr18-46559516-C-A
• rs1555679863
• NM_001384474.1:c.3148G>T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001384474.1(LOXHD1):​c.3148G>T​(p.Glu1050*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000143 in 1,399,768 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: LOXHD1 NM_001384474.1 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 4.92

Genes affected

LOXHD1 (HGNC:26521): (lipoxygenase homology PLAT domains 1) This gene encodes a highly conserved protein consisting entirely of PLAT (polycystin/lipoxygenase/alpha-toxin) domains, thought to be involved in targeting proteins to the plasma membrane. Studies in mice show that this gene is expressed in the mechanosensory hair cells in the inner ear, and mutations in this gene lead to auditory defects, indicating that this gene is essential for normal hair cell function. Screening of human families segregating deafness identified a mutation in this gene which causes DFNB77, a progressive form of autosomal-recessive nonsyndromic hearing loss (ARNSHL). Alternatively spliced transcript variants encoding different isoforms have been noted for this gene. [provided by RefSeq, Mar 2010]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 18-46559516-C-A is Pathogenic according to our data. Variant chr18-46559516-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 505330.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LOXHD1	NM_001384474.1	c.3148G>T	p.Glu1050*	stop_gained	Exon 20 of 41	ENST00000642948.1	NP_001371403.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LOXHD1	ENST00000642948.1	c.3148G>T	p.Glu1050*	stop_gained	Exon 20 of 41		NM_001384474.1	ENSP00000496347.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000143 AC: 2 AN: 1399768 Hom.: 0 Cov.: 33 AF XY: 0.00000290 AC XY: 2 AN XY: 690386

Gnomad4 AFR exome AF: 0.0000316

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000172

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Nonsyndromic genetic hearing loss Pathogenic:1

Mar 30, 2023

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: LOXHD1 c.3148G>T (p.Glu1050X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic in ClinVar. The variant was absent in 159756 control chromosomes (gnomAD). To our knowledge, no occurrence of c.3148G>T in individuals affected with Nonsyndromic Hearing Loss And Deafness, Type 77 and no experimental evidence demonstrating its impact on protein function have been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

not provided Pathogenic:1

Sep 10, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 505330). This variant has not been reported in the literature in individuals affected with LOXHD1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Glu1050*) in the LOXHD1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in LOXHD1 are known to be pathogenic (PMID: 19732867, 21465660, 25792669). -

Rare genetic deafness Pathogenic:1

Oct 25, 2016

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Glu1050X variant in LOXHD1 has not been previously reported in individuals with hearing loss or in large population studies. This nonsense variant leads t o a premature termination codon at position 1050, which is predicted to lead to a truncated or absent protein. Loss of function of the LOXHD1 gene is an establi shed disease mechanism in autosomal recessive hearing loss. In summary, this var iant meets criteria to be classified as pathogenic for autosomal recessive heari ng loss based on the predicted impact to the protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.055	T
BayesDel_noAF	Benign	-0.16
CADD	Pathogenic	42
DANN	Uncertain	1.0
Eigen	Benign	0.11
Eigen_PC	Benign	0.14
FATHMM_MKL	Uncertain	0.95	D
Vest4		0.36
ClinPred		0.95	D
GERP RS		4.4

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: rs1555679863; hg19: chr18-44139479;