8-24954281-C-T

Position:

• chr8-24954281-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_006158.5(NEFL):​c.1069G>A​(p.Glu357Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,334 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: NEFL NM_006158.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.88

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a region_of_interest Coil 2B (size 115) in uniprot entity NFL_HUMAN there are 15 pathogenic changes around while only 1 benign (94%) in NM_006158.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.883

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NEFL	NM_006158.5	c.1069G>A	p.Glu357Lys	missense_variant	2/4	ENST00000610854.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NEFL	ENST00000610854.2	c.1069G>A	p.Glu357Lys	missense_variant	2/4	1	NM_006158.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461334 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726912

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: 0.00000180

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

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

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

May 12, 2016

This sequence change replaces glutamic acid with lysine at codon 1069 of the NEFL protein (p.Glu357Lys). The glutamic acid residue is highly conserved and there is a small physicochemical difference between glutamic acid and lysine. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a NEFL-related disease. 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. In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. A family study may help clarify the significance of this variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.65
CADD	Pathogenic	32
DANN	Benign	0.92
DEOGEN2	Pathogenic	0.94	D;.;T
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.88	D;D;D
MetaRNN	Pathogenic	0.88	D;D;D
PrimateAI	Pathogenic	0.89	D
Sift4G	Uncertain	0.0090	D;.;D
Polyphen		0.99	D;.;.
Vest4		0.86
MVP		0.80
GERP RS		6.1
Varity_R		0.78
gMVP		0.93

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: rs1060503693; hg19: chr8-24811795;