15-32030931-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_000746.6(CHRNA7):c.89A>G(p.Tyr30Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000889 in 1,461,854 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000089 (0 hom.)
• Consequence: CHRNA7 NM_000746.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.01

Genes affected

CHRNA7 (HGNC:1960): (cholinergic receptor nicotinic alpha 7 subunit) The nicotinic acetylcholine receptors (nAChRs) are members of a superfamily of ligand-gated ion channels that mediate fast signal transmission at synapses. The nAChRs are thought to be hetero-pentamers composed of homologous subunits. The proposed structure for each subunit is a conserved N-terminal extracellular domain followed by three conserved transmembrane domains, a variable cytoplasmic loop, a fourth conserved transmembrane domain, and a short C-terminal extracellular region. The protein encoded by this gene forms a homo-oligomeric channel, displays marked permeability to calcium ions and is a major component of brain nicotinic receptors that are blocked by, and highly sensitive to, alpha-bungarotoxin. Once this receptor binds acetylcholine, it undergoes an extensive change in conformation that affects all subunits and leads to opening of an ion-conducting channel across the plasma membrane. This gene is located in a region identified as a major susceptibility locus for juvenile myoclonic epilepsy and a chromosomal location involved in the genetic transmission of schizophrenia. An evolutionarily recent partial duplication event in this region results in a hybrid containing sequence from this gene and a novel FAM7A gene. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.856

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHRNA7	NM_000746.6	c.89A>G	p.Tyr30Cys	missense_variant	2/10	ENST00000306901.9
CHRNA7	NM_001190455.3	c.176A>G	p.Tyr59Cys	missense_variant	2/10
CHRNA7	XM_011521178.4	c.89A>G	p.Tyr30Cys	missense_variant	2/9
CHRNA7	NR_046324.1	n.201A>G		non_coding_transcript_exon_variant	2/8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHRNA7	ENST00000306901.9	c.89A>G	p.Tyr30Cys	missense_variant	2/10	1	NM_000746.6	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251336 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135878

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 SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000889 AC: 13 AN: 1461854 Hom.: 0 Cov.: 32 AF XY: 0.00000963 AC XY: 7 AN XY: 727236

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000108

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia

Jul 20, 2015

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.58
BayesDel_addAF	Uncertain	0.063	T
BayesDel_noAF	Uncertain	-0.050
Cadd	Pathogenic	27
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.68	D;.;.;.
Eigen	Uncertain	0.64
Eigen_PC	Uncertain	0.54
FATHMM_MKL	Uncertain	0.79	D
LIST_S2	Pathogenic	0.98	D;D;D;D
M_CAP	Pathogenic	0.49	D
MetaRNN	Pathogenic	0.86	D;D;D;D
MetaSVM	Uncertain	0.56	D
MutationAssessor	Pathogenic	3.2	M;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-2.4	N;N;.;.
REVEL	Pathogenic	0.78
Sift	Uncertain	0.0010	D;D;.;.
Sift4G	Uncertain	0.0020	D;D;.;.
Polyphen		1.0	D;.;.;.
Vest4		0.82
MutPred		0.63		Gain of methylation at K31 (P = 0.0135);.;Gain of methylation at K31 (P = 0.0135);.;
MVP		0.81
ClinPred		0.90	D
GERP RS		4.4
Varity_R		0.30
gMVP		0.61

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: rs749361514; hg19: chr15-32323134;