1-204944335-C-T

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 3P and 4B. PM2 PP2 BP4_Strong

The NM_001005388.3(NFASC):c.20C>T(p.Pro7Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000161 in 1,613,674 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000016 (0 hom.)
• Consequence: NFASC NM_001005388.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.404

Genes affected

NFASC (HGNC:29866): (neurofascin) This gene encodes an L1 family immunoglobulin cell adhesion molecule with multiple IGcam and fibronectin domains. The protein functions in neurite outgrowth, neurite fasciculation, and organization of the axon initial segment (AIS) and nodes of Ranvier on axons during early development. Both the AIS and nodes of Ranvier contain high densities of voltage-gated Na+ (Nav) channels which are clustered by interactions with cytoskeletal and scaffolding proteins including this protein, gliomedin, ankyrin 3 (ankyrin-G), and betaIV spectrin. This protein links the AIS extracellular matrix to the intracellular cytoskeleton. This gene undergoes extensive alternative splicing, and the full-length nature of some variants has not been determined.[provided by RefSeq, May 2009]

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, NFASC
• BP4: Computational evidence support a benign effect (MetaRNN=0.06327212).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NFASC	NM_001005388.3	c.20C>T	p.Pro7Leu	missense_variant	3/30	ENST00000339876.11
NFASC	NM_001160331.2	c.20C>T	p.Pro7Leu	missense_variant	2/28	ENST00000539706.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NFASC	ENST00000339876.11	c.20C>T	p.Pro7Leu	missense_variant	3/30	5	NM_001005388.3
NFASC	ENST00000539706.6	c.20C>T	p.Pro7Leu	missense_variant	2/28	5	NM_001160331.2	A2

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152216 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000361 AC: 9 AN: 249420 Hom.: 0 AF XY: 0.0000148 AC XY: 2 AN XY: 134978

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000203

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000545

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000888

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000164 AC: 24 AN: 1461458 Hom.: 0 Cov.: 32 AF XY: 0.0000179 AC XY: 13 AN XY: 726986

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000134

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000756

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000108

Gnomad4 OTH exome AF: 0.0000497

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152216 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74362

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000386 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.0000247 AC: 3

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 25, 2023

The c.20C>T (p.P7L) alteration is located in exon 3 (coding exon 1) of the NFASC gene. This alteration results from a C to T substitution at nucleotide position 20, causing the proline (P) at amino acid position 7 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.28
Cadd	Benign	20
Dann	Benign	0.78
Eigen	Benign	-0.47
Eigen_PC	Benign	-0.31
FATHMM_MKL	Benign	0.22	N
LIST_S2	Uncertain	0.91	D;D;D;D;D;.;D;.;.
M_CAP	Benign	0.050	D
MetaRNN	Benign	0.063	T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.37	T
MutationAssessor	Benign	0.34	N;N;N;N;N;N;.;N;N
MutationTaster	Benign	0.85	D;D;D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	1.1	N;N;N;N;N;N;N;N;N
REVEL	Benign	0.14
Sift	Benign	0.77	T;T;T;T;T;T;T;T;T
Sift4G	Benign	1.0	T;T;T;T;T;T;T;T;T
Polyphen		0.99	D;B;B;B;.;D;.;B;B
Vest4		0.19
MVP		0.72
MPC		1.2
ClinPred		0.12	T
GERP RS		4.3
gMVP		0.56

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: rs763285862; hg19: chr1-204913463;