Genetic Variant CHRNA6:p.Ile327Thr (chr8-42756219-A-G) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

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

The NM_004198.3(CHRNA6):c.980T>C(p.Ile327Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,614,124 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

CHRNA6
NM_004198.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.42

Variant links:

Genes affected

CHRNA6 (HGNC:15963): (cholinergic receptor nicotinic alpha 6 subunit) This gene encodes an alpha subunit of neuronal nicotinic acetylcholine receptors. These receptors consist of five subunits and function as ion channels involved in neurotransmission. The encoded protein is a subunit of neuronal nicotinic acetylcholine receptors that mediate dopaminergic neurotransmission and are activated by acetylcholine and exogenous nicotine. Alternatively spliced transcript variants have been observed for this gene. Single nucleotide polymorphisms in this gene have been associated with both nicotine and alcohol dependence. [provided by RefSeq, Dec 2010]

CHRNA6 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHRNA6	NM_004198.3 link	c.980T>C	p.Ile327Thr	missense_variant	Exon 5 of 6	ENST00000276410.7	NP_004189.1	Q15825-1
CHRNA6	NM_001199279.1 link	c.935T>C	p.Ile312Thr	missense_variant	Exon 4 of 5		NP_001186208.1	Q15825-2
CHRNA6	XM_047422396.1 link	c.980T>C	p.Ile327Thr	missense_variant	Exon 6 of 7		XP_047278352.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHRNA6	ENST00000276410.7 link	c.980T>C	p.Ile327Thr	missense_variant	Exon 5 of 6	1	NM_004198.3	ENSP00000276410.3		Q15825-1
CHRNA6	ENST00000534622.5 link	c.935T>C	p.Ile312Thr	missense_variant	Exon 4 of 5	2		ENSP00000433871.1		Q15825-2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152236

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251468

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135910

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS 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:

0.00000274

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000671

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

AF:

0.0000131

AC:

AN:

152236

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74382

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Feb 06, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.980T>C (p.I327T) alteration is located in exon 5 (coding exon 5) of the CHRNA6 gene. This alteration results from a T to C substitution at nucleotide position 980, causing the isoleucine (I) at amino acid position 327 to be replaced by a threonine (T). 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

Pathogenic

0.71

BayesDel_addAF

Uncertain

0.049

BayesDel_noAF

Uncertain

-0.080

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.72

D;.

Eigen

Uncertain

0.45

Eigen_PC

Uncertain

0.50

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.81

T;T

M_CAP

Benign

0.054

MetaRNN

Uncertain

0.61

D;D

MetaSVM

Uncertain

0.27

MutationAssessor

Pathogenic

3.2

M;.

PrimateAI

Uncertain

0.69

PROVEAN

Uncertain

-3.4

D;D

REVEL

Pathogenic

0.70

Sift

Benign

0.053

T;D

Sift4G

Benign

0.093

T;T

Polyphen

0.96

D;.

Vest4

0.19

MutPred

0.79

Gain of disorder (P = 0.0149);.;

MVP

0.88

MPC

0.15

ClinPred

0.84

GERP RS

4.8

Varity_R

0.49

gMVP

0.48

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over