Genetic Variant LRAT:p.Glu14* (chr4-154744366-G-T) – ACMG Classification: Likely_pathogenic (8 pts)

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_StrongPM2PP5_Moderate

The NM_004744.5(LRAT):c.40G>T(p.Glu14*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,614,032 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

LRAT
NM_004744.5 stop_gained

Scores

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 7.33

Variant links:

Genes affected

LRAT (HGNC:6685): (lecithin retinol acyltransferase) The protein encoded by this gene localizes to the endoplasmic reticulum, where it catalyzes the esterification of all-trans-retinol into all-trans-retinyl ester. This reaction is an important step in vitamin A metabolism in the visual system. Mutations in this gene have been associated with early-onset severe retinal dystrophy and Leber congenital amaurosis 14. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2014]

LRAT links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 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. There are 17 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 4-154744366-G-T is Pathogenic according to our data. Variant chr4-154744366-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 667379.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LRAT	NM_004744.5 link	c.40G>T	p.Glu14*	stop_gained	Exon 2 of 3	ENST00000336356.4	NP_004735.2	O95237
LRAT	NM_001301645.2 link	c.40G>T	p.Glu14*	stop_gained	Exon 2 of 3		NP_001288574.1	O95237
LRAT	XM_047416405.1 link	c.40G>T	p.Glu14*	stop_gained	Exon 2 of 3		XP_047272361.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LRAT	ENST00000336356.4 link	c.40G>T	p.Glu14*	stop_gained	Exon 2 of 3	1	NM_004744.5	ENSP00000337224.3		O95237

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152164

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1461868

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727236

show subpopulations

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:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000450

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152164

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74322

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Leber congenital amaurosis

Pathogenic:1

Dec 27, 2018

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Glu14X variant in LRAT has not been previously reported in individuals wit h Leber congenital amaurosis and was absent from large population studies. This nonsense variant leads to a premature termination codon at position 14, which is predicted to lead to a truncated or absent protein. Loss of function of the LRA T gene is strongly associated with autosomal recessive Leber congenital amaurosi s. In summary, although additional studies are required to fully establish its c linical significance, this variant meets criteria to be classified as likely pat hogenic for Leber congenital amaurosis in an autosomal recessive manner. ACMG/AM P Criteria applied: PVS1_Strong, PM2. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.55

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

0.76

Eigen_PC

Uncertain

0.56

FATHMM_MKL

Pathogenic

0.97

Vest4

0.66

GERP RS

4.4

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.20

Details are displayed if max score is > 0.2

DS_AL_spliceai

0.20

Position offset: -40

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over