X-12885591-G-T

Position:

• chrX-12885591-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM2 PM5 BP4_Moderate

The NM_016562.4(TLR7):​c.83G>T​(p.Arg28Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R28G) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 24)
• Consequence: TLR7 NM_016562.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.272

Genes affected

TLR7 (HGNC:15631): (toll like receptor 7) The protein encoded by this gene is a member of the Toll-like receptor (TLR) family which plays a fundamental role in pathogen recognition and activation of innate immunity. TLRs are highly conserved from Drosophila to humans and share structural and functional similarities. The human TLR family comprises 11 members. They recognize pathogen-associated molecular patterns (PAMPs) that are expressed on infectious agents, and mediate the production of cytokines necessary for the development of effective immunity. For the recognition of structural components in foreign microorganisms, the various TLRs exhibit different patterns of expression as well; in this way for example, TLR-3, -7, and -8 are essential in the recognition of single-stranded RNA viruses. TLR7 senses single-stranded RNA oligonucleotides containing guanosine- and uridine-rich sequences from RNA viruses, a recognition occuring in the endosomes of plasmacytoid dendritic cells and B cells. This gene is predominantly expressed in lung, placenta, and spleen, and is phylogenetically related and lies in close proximity to another family member, TLR8, on chromosome X. [provided by RefSeq, Aug 2020]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• BP4: Computational evidence support a benign effect (MetaRNN=0.11273706).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TLR7	NM_016562.4	c.83G>T	p.Arg28Ile	missense_variant	3/3	ENST00000380659.4	NP_057646.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TLR7	ENST00000380659.4	c.83G>T	p.Arg28Ile	missense_variant	3/3	1	NM_016562.4	ENSP00000370034	P1

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 24

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

Dec 02, 2023

This sequence change replaces arginine, which is basic and polar, with isoleucine, which is neutral and non-polar, at codon 28 of the TLR7 protein (p.Arg28Ile). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TLR7-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The isoleucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.33	T
BayesDel_noAF	Benign	-0.71
CADD	Benign	16
DANN	Benign	0.95
DEOGEN2	Benign	0.080	T
FATHMM_MKL	Benign	0.098	N
LIST_S2	Uncertain	0.91	D
M_CAP	Benign	0.010	T
MetaRNN	Benign	0.11	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.2	L
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.31	T
PROVEAN	Benign	0.13	N
REVEL	Benign	0.045
Sift	Benign	0.16	T
Sift4G	Benign	0.25	T
Polyphen		0.0	B
Vest4		0.14
MutPred		0.61		Gain of ubiquitination at K32 (P = 0.0556);
MVP		0.32
MPC		1.2
ClinPred		0.043	T
GERP RS		2.7
Varity_R		0.082
gMVP		0.40

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

No publications associated with this variant yet.

Other links and lift over

hg19: chrX-12903710;