1-115286134-C-A

Position:

• chr1-115286134-C-A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_002506.3(NGF):​c.662G>T​(p.Arg221Leu) variant causes a missense change involving the alteration of a 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R221W) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NGF NM_002506.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.86

Genes affected

NGF (HGNC:7808): (nerve growth factor) This gene is a member of the NGF-beta family and encodes a secreted protein which homodimerizes and is incorporated into a larger complex. This protein has nerve growth stimulating activity and the complex is involved in the regulation of growth and the differentiation of sympathetic and certain sensory neurons. Mutations in this gene have been associated with hereditary sensory and autonomic neuropathy, type 5 (HSAN5), and dysregulation of this gene's expression is associated with allergic rhinitis. [provided by RefSeq, Jul 2008]

NGF-AS1 (HGNC:53922): (NGF antisense RNA 1)

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-115286135-G-A is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.989

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NGF	NM_002506.3	c.662G>T	p.Arg221Leu	missense_variant	3/3	ENST00000369512.3	NP_002497.2
NGF-AS1	NR_157569.1	n.207+2894C>A		intron_variant, non_coding_transcript_variant
NGF	XM_011541518.3	c.827G>T	p.Arg276Leu	missense_variant	3/3		XP_011539820.1
NGF	XM_006710663.4	c.662G>T	p.Arg221Leu	missense_variant	2/2		XP_006710726.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NGF	ENST00000369512.3	c.662G>T	p.Arg221Leu	missense_variant	3/3	1	NM_002506.3	ENSP00000358525	P1
NGF-AS1	ENST00000425449.1	n.207+2894C>A		intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital sensory neuropathy with selective loss of small myelinated fibers Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 24, 2019

This variant has not been reported in the literature in individuals with NGF-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. This variant disrupts the p.Arg221 (also known as p.Arg100 in the literature) amino acid residue in NGF. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 14976160, 18420729, 19038341, 19945432, 20978020, 21387003). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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 arginine with leucine at codon 221 of the NGF protein (p.Arg221Leu). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and leucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.54	D
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.19	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	0.25	D
MutationAssessor	Pathogenic	3.0	M
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-4.5	D
REVEL	Pathogenic	0.88
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.91		Loss of MoRF binding (P = 0.0031);
MVP		0.94
MPC		1.2
ClinPred		1.0	D
GERP RS		4.9
Varity_R		0.75
gMVP		0.94

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: rs1432643322; hg19: chr1-115828755;