22-20982374-G-A

Position:

• chr22-20982374-G-A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_006767.4(LZTR1):​c.3G>A​(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: LZTR1 NM_006767.4 start_lost
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 3.33

Genes affected

LZTR1 (HGNC:6742): (leucine zipper like post translational regulator 1) This gene encodes a member of the BTB-kelch superfamily. Initially described as a putative transcriptional regulator based on weak homology to members of the basic leucine zipper-like family, the encoded protein subsequently has been shown to localize exclusively to the Golgi network where it may help stabilize the Gogli complex. Deletion of this gene may be associated with DiGeorge syndrome. [provided by RefSeq, Jul 2008]

LZTR1 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Start lost variant, no new inframe start found.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 22-20982374-G-A is Pathogenic according to our data. Variant chr22-20982374-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 3238279.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LZTR1	NM_006767.4	c.3G>A	p.Met1?	start_lost	1/21	ENST00000646124.2	NP_006758.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LZTR1	ENST00000646124.2	c.3G>A	p.Met1?	start_lost	1/21		NM_006767.4	ENSP00000496779.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

May 12, 2023

The p.M1? pathogenic mutation (also known as c.3G>A) is located in coding exon 1 of the LZTR1 gene and results from a G to A substitution at nucleotide position 3. This alters the methionine residue at the initiation codon (ATG). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Sequence variations that modify the initiation codon are expected to result in either loss of translation initiation, N-terminal truncation, or cause a shift in the mRNA reading frame. Loss-of-function variants in LZTR1 are related to an increased risk for schwannomas and autosomal recessive Noonan syndrome; however, such associations with autosomal dominant Noonan syndrome have not been observed (Piotrowski A et al. Nat Genet. 2014 Feb;46:182-7; Yamamoto GL et al. J Med Genet. 2015 Jun;52:413-21; Johnston JJ et al. Genet Med. 2018 10;20:1175-1185). Based on the supporting evidence, this variant is pathogenic for an increased risk of LZTR1-related schwannomatosis (SWN) and would be expected to cause autosomal recessive Noonan syndrome when present along with a second pathogenic or likely pathogenic variant on the other allele; however, the association of this alteration with autosomal dominant Noonan syndrome is unlikely. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Benign	-0.31
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.025	T;T;.
Eigen	Benign	-0.021
Eigen_PC	Benign	0.13
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Uncertain	0.90	.;D;D
M_CAP	Pathogenic	0.42	D
MetaRNN	Pathogenic	0.95	D;D;D
MetaSVM	Benign	-1.0	T
PROVEAN	Benign	-0.080	N;.;.
REVEL	Benign	0.16
Sift	Benign	0.045	D;.;.
Sift4G	Benign	0.13	T;.;.
Polyphen		0.067	B;B;.
Vest4		0.65
MutPred		0.85		Loss of glycosylation at P4 (P = 0.0873);Loss of glycosylation at P4 (P = 0.0873);Loss of glycosylation at P4 (P = 0.0873);
MVP		0.17
ClinPred		0.98	D
GERP RS		5.2
RBP_binding_hub_radar		0.97
RBP_regulation_power_radar		2.8
Varity_R		0.48
gMVP		0.47

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: rs1214659869; hg19: chr22-21336663;