rs74315314

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1PM2PM5PP2PP3_Moderate

The NM_020435.4(GJC2):​c.814T>C​(p.Tyr272His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,584 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y272D) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

GJC2
NM_020435.4 missense

Scores

12
6
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.43

Publications

7 publications found
Variant links:
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]
GJC2 Gene-Disease associations (from GenCC):
  • hypomyelinating leukodystrophy 2
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • lymphatic malformation 3
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • hereditary spastic paraplegia 44
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
  • lymphatic malformation
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 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, 3 uncertain in NM_020435.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-228158572-T-G is described in ClinVar as [Pathogenic]. Clinvar id is 2075.Status of the report is no_assertion_criteria_provided, 0 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 19 curated pathogenic missense variants (we use a threshold of 10). The gene has 3 curated benign missense variants. Gene score misZ: 1.8719 (below the threshold of 3.09). Trascript score misZ: -1.3976 (below the threshold of 3.09). GenCC associations: The gene is linked to hypomyelinating leukodystrophy 2, hereditary spastic paraplegia 44, lymphatic malformation 3, lymphatic malformation.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.921

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GJC2NM_020435.4 linkc.814T>C p.Tyr272His missense_variant Exon 2 of 2 ENST00000366714.3 NP_065168.2 Q5T442A0A654IBV7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GJC2ENST00000366714.3 linkc.814T>C p.Tyr272His missense_variant Exon 2 of 2 1 NM_020435.4 ENSP00000355675.2 Q5T442

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000400
AC:
1
AN:
250004
AF XY:
0.00000738
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460584
Hom.:
0
Cov.:
36
AF XY:
0.00000138
AC XY:
1
AN XY:
726676
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33438
American (AMR)
AF:
0.00
AC:
0
AN:
44702
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26100
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39674
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52744
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111568
Other (OTH)
AF:
0.00
AC:
0
AN:
60338
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Hypomyelinating leukodystrophy 2 Uncertain:1
-
Neuberg Centre For Genomic Medicine, NCGM
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The missense c.814T>C (p.Tyr272His) variant in GJC2 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The variant is observed in 0.0004% alleles in gnomAD Exomes and is novel (not in any individuals) in 1000 Genomes. The amino acid Tyr at position 272 is changed to a His changing protein sequence and it might alter its composition and physico-chemical properties. The amino acid change p.Tyr272His in GJC2 is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.25
D
BayesDel_noAF
Pathogenic
0.22
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.82
D
Eigen
Uncertain
0.62
Eigen_PC
Uncertain
0.53
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.86
D
M_CAP
Pathogenic
0.77
D
MetaRNN
Pathogenic
0.92
D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Uncertain
2.4
M
PhyloP100
7.4
PrimateAI
Pathogenic
0.92
D
PROVEAN
Uncertain
-4.3
D
REVEL
Pathogenic
0.91
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.75
MutPred
0.68
Loss of stability (P = 0.0585);
MVP
0.97
ClinPred
0.93
D
GERP RS
3.9
Varity_R
0.84
gMVP
0.91
Mutation Taster
=39/61
disease causing

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

Other links and lift over

dbSNP: rs74315314; hg19: chr1-228346273; API