4-40335489-A-T

Position:

• chr4-40335489-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_017581.4(CHRNA9):​c.22A>T​(p.Ile8Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign 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. I8T) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CHRNA9 NM_017581.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.286

Genes affected

CHRNA9 (HGNC:14079): (cholinergic receptor nicotinic alpha 9 subunit) This gene is a member of the ligand-gated ionic channel family and nicotinic acetylcholine receptor gene superfamily. It encodes a plasma membrane protein that forms homo- or hetero-oligomeric divalent cation channels. This protein is involved in cochlea hair cell development and is also expressed in the outer hair cells (OHCs) of the adult cochlea. [provided by RefSeq, Feb 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.099595815).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHRNA9	NM_017581.4	c.22A>T	p.Ile8Phe	missense_variant	1/5	ENST00000310169.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHRNA9	ENST00000310169.3	c.22A>T	p.Ile8Phe	missense_variant	1/5	1	NM_017581.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

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

Ambry Genetics

May 02, 2024

The c.22A>T (p.I8F) alteration is located in exon 1 (coding exon 1) of the CHRNA9 gene. This alteration results from a A to T substitution at nucleotide position 22, causing the isoleucine (I) at amino acid position 8 to be replaced by a phenylalanine (F). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.050
BayesDel_addAF	Benign	-0.11	T
BayesDel_noAF	Benign	-0.40
CADD	Benign	8.1
DANN	Benign	0.76
DEOGEN2	Benign	0.11	T
Eigen	Benign	-1.3
Eigen_PC	Benign	-1.2
FATHMM_MKL	Benign	0.20	N
LIST_S2	Benign	0.48	T
M_CAP	Benign	0.0095	T
MetaRNN	Benign	0.10	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	N
MutationTaster	Benign	0.69	D
PrimateAI	Benign	0.47	T
PROVEAN	Benign	-0.68	N
REVEL	Uncertain	0.30
Sift	Benign	0.41	T
Sift4G	Benign	0.12	T
Polyphen		0.0	B
Vest4		0.27
MutPred		0.55		Loss of helix (P = 0.079);
MVP		0.27
MPC		0.10
ClinPred		0.048	T
GERP RS		-7.2
Varity_R		0.076
gMVP		0.36

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr4-40337506;