chr8-24955828-C-T

Position:

• chr8-24955828-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_006158.5(NEFL):​c.688G>A​(p.Glu230Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000013 in 1,459,188 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E230D) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000013 (0 hom.)
• Consequence: NEFL NM_006158.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.09

Genes affected

NEFL (HGNC:7739): (neurofilament light chain) Neurofilaments are type IV intermediate filament heteropolymers composed of light, medium, and heavy chains. Neurofilaments comprise the axoskeleton and they functionally maintain the neuronal caliber. They may also play a role in intracellular transport to axons and dendrites. This gene encodes the light chain neurofilament protein. Mutations in this gene cause Charcot-Marie-Tooth disease types 1F (CMT1F) and 2E (CMT2E), disorders of the peripheral nervous system that are characterized by distinct neuropathies. A pseudogene has been identified on chromosome Y. [provided by RefSeq, Oct 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.917

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NEFL	NM_006158.5	c.688G>A	p.Glu230Lys	missense_variant	1/4	ENST00000610854.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NEFL	ENST00000610854.2	c.688G>A	p.Glu230Lys	missense_variant	1/4	1	NM_006158.5	P1
NEFL	ENST00000615973.1	n.894G>A		non_coding_transcript_exon_variant	1/1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.0000130 AC: 19 AN: 1459188 Hom.: 0 Cov.: 36 AF XY: 0.0000110 AC XY: 8 AN XY: 726048

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: 0.0000126

Gnomad4 OTH exome AF: 0.0000828

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000936 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 22, 2022

The p.E230K variant (also known as c.688G>A), located in coding exon 1 of the NEFL gene, results from a G to A substitution at nucleotide position 688. The glutamic acid at codon 230 is replaced by lysine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Charcot-Marie-Tooth disease type 2E Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 14, 2023

ClinVar contains an entry for this variant (Variation ID: 412302). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt NEFL 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. This variant has not been reported in the literature in individuals affected with NEFL-related conditions. This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 230 of the NEFL protein (p.Glu230Lys). This variant is not present in population databases (gnomAD no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	35
DANN	Benign	0.97
DEOGEN2	Pathogenic	0.93	D
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Pathogenic	1.0	D
MetaRNN	Pathogenic	0.92	D
PrimateAI	Uncertain	0.71	T
Sift4G	Uncertain	0.0040	D
Polyphen		1.0	D
Vest4		0.80
MVP		0.74
GERP RS		5.3
Varity_R		0.78
gMVP		0.92

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: rs758201328; hg19: chr8-24813342;