1-161305719-G-C

Variant names:

• chr1-161305719-G-C
• rs960768823
• ENST00000463290.5:n.*157C>G

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_Strong BP6 BS2_Supporting

The NM_000530.8(MPZ):​c.*157C>G variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000146 in 615,218 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (no stars).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 31)
  • Exomes 𝑓: 0.000011 (0 hom.)
• Consequence: MPZ NM_000530.8 3_prime_UTR
• Clinical Significance: Likely benign no assertion criteria provided B:1
• Conservation: PhyloP100: 2.57
• Publications: 0 publications found

Genes affected

MPZ (HGNC:7225): (myelin protein zero) This gene is specifically expressed in Schwann cells of the peripheral nervous system and encodes a type I transmembrane glycoprotein that is a major structural protein of the peripheral myelin sheath. The encoded protein contains a large hydrophobic extracellular domain and a smaller basic intracellular domain, which are essential for the formation and stabilization of the multilamellar structure of the compact myelin. Mutations in this gene are associated with autosomal dominant form of Charcot-Marie-Tooth disease type 1 (CMT1B) and other polyneuropathies, such as Dejerine-Sottas syndrome (DSS) and congenital hypomyelinating neuropathy (CHN). A recent study showed that two isoforms are produced from the same mRNA by use of alternative in-frame translation termination codons via a stop codon readthrough mechanism. [provided by RefSeq, Oct 2015]

MPZ Gene-Disease associations (from GenCC):

• Charcot-Marie-Tooth disease

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• Charcot-Marie-Tooth disease type 1B

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, Orphanet
• neuropathy, congenital hypomyelinating, 2

  Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
• autosomal dominant intermediate Charcot-Marie-Tooth disease with neuropathic pain

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Charcot-Marie-Tooth disease dominant intermediate D

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Charcot-Marie-Tooth disease type 2I

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Charcot-Marie-Tooth disease type 2J

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Charcot-Marie-Tooth disease type 3

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -6 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.49).
• BP6: Variant 1-161305719-G-C is Benign according to our data. Variant chr1-161305719-G-C is described in ClinVar as [Likely_benign]. Clinvar id is 3358506.Status of the report is no_assertion_criteria_provided, 0 stars.
• BS2: High AC in GnomAdExome4 at 5 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MPZ	NM_000530.8	c.*157C>G		3_prime_UTR_variant	Exon 6 of 6	ENST00000533357.5	NP_000521.2
MPZ	NM_001315491.2	c.904C>G	p.Leu302Val	missense_variant	Exon 6 of 6		NP_001302420.1
MPZ	XM_017001321.3	c.675+389C>G		intron_variant	Intron 5 of 5		XP_016856810.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MPZ	ENST00000533357.5	c.*157C>G		3_prime_UTR_variant	Exon 6 of 6	1	NM_000530.8	ENSP00000432943.1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152026 Hom.: 0 Cov.: 31

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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000589

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000108 AC: 5 AN: 463192 Hom.: 0 Cov.: 5 AF XY: 0.00000410 AC XY: 1 AN XY: 244130

African (AFR) AF: 0.00 AC: 0 AN: 12638

American (AMR) AF: 0.00 AC: 0 AN: 18924

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 13792

East Asian (EAS) AF: 0.00 AC: 0 AN: 31374

South Asian (SAS) AF: 0.00 AC: 0 AN: 45938

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 32666

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 1992

European-Non Finnish (NFE) AF: 0.0000179 AC: 5 AN: 279430

Other (OTH) AF: 0.00 AC: 0 AN: 26438

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152026 Hom.: 0 Cov.: 31 AF XY: 0.0000135 AC XY: 1 AN XY: 74234

African (AFR) AF: 0.00 AC: 0 AN: 41398

American (AMR) AF: 0.00 AC: 0 AN: 15270

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5178

South Asian (SAS) AF: 0.00 AC: 0 AN: 4820

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.0000589 AC: 4 AN: 67966

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000264

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: no assertion criteria provided

Submissions by phenotype

MPZ-related disorder Benign:1

Jun 27, 2024

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.49
CADD	Benign	20
DANN	Benign	0.86
PhyloP100		2.6
Mutation Taster		=98/2	polymorphism

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

Other links and lift over

dbSNP: rs960768823; hg19: chr1-161275509;