3-45827437-T-C

Position:

• chr3-45827437-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_020347.4(LZTFL1):​c.800A>G​(p.Gln267Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,760 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LZTFL1 NM_020347.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.61

Genes affected

LZTFL1 (HGNC:6741): (leucine zipper transcription factor like 1) This gene encodes a ubiquitously expressed protein that localizes to the cytoplasm. This protein interacts with Bardet-Biedl Syndrome (BBS) proteins and, through its interaction with BBS protein complexes, regulates protein trafficking to the ciliary membrane. Nonsense mutations in this gene cause a form of Bardet-Biedl Syndrome; a ciliopathy characterized in part by polydactyly, obesity, cognitive impairment, hypogonadism, and kidney failure. This gene may also function as a tumor suppressor; possibly by interacting with E-cadherin and the actin cytoskeleton and thereby regulating the transition of epithelial cells to mesenchymal cells. [provided by RefSeq, Aug 2020]

LZTFL1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LZTFL1	NM_020347.4	c.800A>G	p.Gln267Arg	missense_variant	9/10	ENST00000296135.11	NP_065080.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LZTFL1	ENST00000296135.11	c.800A>G	p.Gln267Arg	missense_variant	9/10	1	NM_020347.4	ENSP00000296135.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460760 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 726750

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 23, 2019

This variant has not been reported in the literature in individuals with LZTFL1-related conditions. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant is not present in population databases (ExAC no frequency). This sequence change replaces glutamine with arginine at codon 267 of the LZTFL1 protein (p.Gln267Arg). The glutamine residue is highly conserved and there is a small physicochemical difference between glutamine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.42
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.12
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Benign	0.058	T;.
Eigen	Pathogenic	0.70
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	D;D
M_CAP	Benign	0.028	D
MetaRNN	Uncertain	0.67	D;D
MetaSVM	Benign	-0.92	T
MutationAssessor	Uncertain	2.4	M;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.77	T
PROVEAN	Benign	-2.3	N;N
REVEL	Uncertain	0.43
Sift	Uncertain	0.0050	D;D
Sift4G	Uncertain	0.042	D;D
Polyphen		0.97	D;.
Vest4		0.80
MutPred		0.46		Gain of MoRF binding (P = 0.0166);.;
MVP		0.64
MPC		1.4
ClinPred		0.98	D
GERP RS		5.4
Varity_R		0.48
gMVP		0.49

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		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: rs1700697159; hg19: chr3-45868929;