chr2-174757645-G-A

Position:

• chr2-174757645-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_000079.4(CHRNA1):​c.265C>T​(p.Pro89Ser) 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 Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: CHRNA1 NM_000079.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.91

Genes affected

CHRNA1 (HGNC:1955): (cholinergic receptor nicotinic alpha 1 subunit) The muscle acetylcholine receptor consiststs of 5 subunits of 4 different types: 2 alpha subunits and 1 each of the beta, gamma, and delta subunits. This gene encodes an alpha subunit that plays a role in acetlycholine binding/channel gating. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Nov 2012]

(HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a topological_domain Extracellular (size 211) in uniprot entity ACHA_HUMAN there are 6 pathogenic changes around while only 0 benign (100%) in NM_000079.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.937

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHRNA1	NM_000079.4	c.265C>T	p.Pro89Ser	missense_variant	4/9	ENST00000348749.9	NP_000070.1
CHRNA1	NM_001039523.3	c.340C>T	p.Pro114Ser	missense_variant	5/10		NP_001034612.1
CHRNA1	XM_017003256.2	c.361C>T	p.Pro121Ser	missense_variant	4/9		XP_016858745.1
CHRNA1	XM_017003257.2	c.286C>T	p.Pro96Ser	missense_variant	3/8		XP_016858746.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHRNA1	ENST00000348749.9	c.265C>T	p.Pro89Ser	missense_variant	4/9	1	NM_000079.4	ENSP00000261008	P1
	ENST00000442996.1	n.322-15104G>A		intron_variant, non_coding_transcript_variant		1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

May 10, 2021

Not observed in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.85
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Uncertain	0.13
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.83	.;D;T;T;.
Eigen	Pathogenic	0.93
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.87	D;D;D;D;D
M_CAP	Uncertain	0.11	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D
MetaSVM	Uncertain	0.43	D
MutationAssessor	Uncertain	2.7	.;M;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.55	T
PROVEAN	Pathogenic	-7.5	D;D;D;.;D
REVEL	Pathogenic	0.71
Sift	Uncertain	0.016	D;D;D;.;D
Sift4G	Benign	0.091	T;T;T;.;D
Polyphen		0.94, 0.98	.;P;.;.;D
Vest4		0.90
MutPred		0.74		.;Loss of catalytic residue at P114 (P = 0.0558);.;.;.;
MVP		0.89
MPC		0.38
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.87
gMVP		0.71

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: chr2-175622373; COSMIC: COSV53684424;