rs1553262546

Variant names:

• chr1-228158437-T-A
• rs1553262546
• NM_020435.4:c.679T>A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_020435.4(GJC2):​c.679T>A​(p.Phe227Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: GJC2 NM_020435.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 7.47

Genes affected

GJC2 (HGNC:17494): (gap junction protein gamma 2) This gene encodes a gap junction protein. Gap junction proteins are members of a large family of homologous connexins and comprise 4 transmembrane, 2 extracellular, and 3 cytoplasmic domains. This gene plays a key role in central myelination and is involved in peripheral myelination in humans. Defects in this gene are the cause of autosomal recessive Pelizaeus-Merzbacher-like disease-1. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_020435.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.987
• PP5: Variant 1-228158437-T-A is Pathogenic according to our data. Variant chr1-228158437-T-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 521638.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GJC2	NM_020435.4	c.679T>A	p.Phe227Ile	missense_variant	Exon 2 of 2	ENST00000366714.3	NP_065168.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GJC2	ENST00000366714.3	c.679T>A	p.Phe227Ile	missense_variant	Exon 2 of 2	1	NM_020435.4	ENSP00000355675.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Inborn genetic diseases Pathogenic:1

May 02, 2017

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Aug 20, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.96	D
Eigen	Pathogenic	0.74
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.94	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.2	H
PrimateAI	Pathogenic	0.95	D
PROVEAN	Pathogenic	-6.0	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.88
MutPred		0.87		Loss of sheet (P = 0.1907);
MVP		0.98
ClinPred		1.0	D
GERP RS		4.0
Varity_R		0.92
gMVP		1.0

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: rs1553262546; hg19: chr1-228346138;