rs376797385

chr17-15259095-G-A

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Strong BP6 BP7

The NM_000304.4(PMP22):c.177C>T(p.Asn59=) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000529 in 1,606,886 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000085 (0 hom., cov: 31)
  • Exomes 𝑓: 0.000049 (0 hom.)
• Consequence: PMP22 NM_000304.4 splice_region, synonymous
• Scores: Splicing: ADA: 0.0004982
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: -1.26

Genes affected

PMP22 (HGNC:9118): (peripheral myelin protein 22) This gene encodes an integral membrane protein that is a major component of myelin in the peripheral nervous system. Studies suggest two alternately used promoters drive tissue-specific expression. Various mutations of this gene are causes of Charcot-Marie-Tooth disease Type IA, Dejerine-Sottas syndrome, and hereditary neuropathy with liability to pressure palsies. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.91).
• BP6: Variant 17-15259095-G-A is Benign according to our data. Variant chr17-15259095-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 387578.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.
• BP7: Synonymous conserved (PhyloP=-1.26 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PMP22	NM_000304.4	c.177C>T	p.Asn59=	splice_region_variant, synonymous_variant	3/5	ENST00000312280.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PMP22	ENST00000312280.9	c.177C>T	p.Asn59=	splice_region_variant, synonymous_variant	3/5	1	NM_000304.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000854 AC: 13 AN: 152188 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.0000483

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000162

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000438 AC: 11 AN: 251254 Hom.: 0 AF XY: 0.0000295 AC XY: 4 AN XY: 135784

Gnomad AFR exome AF: 0.000123

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000655

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000616

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000495 AC: 72 AN: 1454698 Hom.: 0 Cov.: 30 AF XY: 0.0000400 AC XY: 29 AN XY: 724200

Gnomad4 AFR exome AF: 0.0000900

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000813

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000543

Gnomad4 OTH exome AF: 0.0000333

GnomAD4 genome AF: 0.0000854 AC: 13 AN: 152188 Hom.: 0 Cov.: 31 AF XY: 0.0000538 AC XY: 4 AN XY: 74354

Gnomad4 AFR AF: 0.0000483

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000162

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000138 Hom.: 0

Bravo AF: 0.0000869

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Charcot-Marie-Tooth disease, type I Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 30, 2023

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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. ClinVar contains an entry for this variant (Variation ID: 387578). This variant has not been reported in the literature in individuals affected with PMP22-related conditions. This variant is present in population databases (rs376797385, gnomAD 0.02%). This sequence change affects codon 59 of the PMP22 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the PMP22 protein. It affects a nucleotide within the consensus splice site. -

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Dec 17, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.91
Cadd	Benign	1.2
Dann	Benign	0.71

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00050
dbscSNV1_RF	Benign	0.090
SpliceAI score (max)		0.020		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: rs376797385; hg19: chr17-15162412;