rs1554201017

chr6-121447236-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Moderate PP5_Moderate

The NM_000165.5(GJA1):c.389T>C(p.Ile130Thr) 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 Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: GJA1 NM_000165.5 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.67

Genes affected

GJA1 (HGNC:4274): (gap junction protein alpha 1) This gene is a member of the connexin gene family. The encoded protein is a component of gap junctions, which are composed of arrays of intercellular channels that provide a route for the diffusion of low molecular weight materials from cell to cell. The encoded protein is the major protein of gap junctions in the heart that are thought to have a crucial role in the synchronized contraction of the heart and in embryonic development. A related intronless pseudogene has been mapped to chromosome 5. Mutations in this gene have been associated with oculodentodigital dysplasia, autosomal recessive craniometaphyseal dysplasia and heart malformations. [provided by RefSeq, May 2014]

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, 3 uncertain in NM_000165.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, GJA1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.844
• PP5: Variant 6-121447236-T-C is Pathogenic according to our data. Variant chr6-121447236-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 470215.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr6-121447236-T-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GJA1	NM_000165.5	c.389T>C	p.Ile130Thr	missense_variant	2/2	ENST00000282561.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GJA1	ENST00000282561.4	c.389T>C	p.Ile130Thr	missense_variant	2/2	1	NM_000165.5	P1
GJA1	ENST00000647564.1	c.389T>C	p.Ile130Thr	missense_variant	2/2			P1
GJA1	ENST00000649003.1	c.389T>C	p.Ile130Thr	missense_variant	2/2			P1
GJA1	ENST00000650427.1	c.389T>C	p.Ile130Thr	missense_variant	2/2			P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 6.84e-7 AC: 1 AN: 1461844 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727226

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Oculodentodigital dysplasia, autosomal recessive Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Dec 10, 2023

This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 130 of the GJA1 protein (p.Ile130Thr). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with oculodentodigital dysplasia (PMID: 12457340, 18660473, 22826718). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 470215). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt GJA1 protein function with a negative predictive value of 80%. Experimental studies have shown that this missense change affects GJA1 function (PMID: 15879313, 18077386). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.49
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.46
Cadd	Benign	21
Dann	Benign	0.94
DEOGEN2	Uncertain	0.67	D;D;D;D;D
Eigen	Benign	-0.041
Eigen_PC	Benign	0.091
FATHMM_MKL	Uncertain	0.93	D
M_CAP	Uncertain	0.12	D
MetaRNN	Pathogenic	0.84	D;D;D;D;D
MetaSVM	Uncertain	0.58	D
MutationAssessor	Uncertain	2.3	M;M;M;M;M
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.77	T
Polyphen		0.012	B;B;B;B;B
Vest4		0.70
MutPred		0.76		Gain of disorder (P = 0.0363);Gain of disorder (P = 0.0363);Gain of disorder (P = 0.0363);Gain of disorder (P = 0.0363);Gain of disorder (P = 0.0363);
MVP		1.0
MPC		0.64
ClinPred		0.63	D
GERP RS		5.2
Varity_R		0.28
gMVP		0.87

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: rs1554201017; hg19: chr6-121768382;