15-78625057-A-T

Position:

• chr15-78625057-A-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_001256567.3(CHRNB4):​c.594T>A​(p.Ala198Ala) variant causes a synonymous 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CHRNB4 NM_001256567.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.921

Genes affected

CHRNB4 (HGNC:1964): (cholinergic receptor nicotinic beta 4 subunit) This gene is found within a conserved gene cluster and encodes one of the beta subunits of the nicotinic acetylcholine receptor (nAChRs) superfamily which form ligand-gated ion channels with a central pore that forms a cation channel. Neuronal nAChRs are pentameric structures that can be either homomeric or heteromeric, with heteromeric structures containing both alpha and beta subunits. Each subunit contains an extracellular amino terminus and four transmembrane domains. Nicotine is one of the agonists that binds to the receptor. Variants in this gene have been associated with nicotine dependence and lung cancer. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Sep 2017]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP7: Synonymous conserved (PhyloP=-0.921 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHRNB4	NM_000750.5	c.*76T>A		3_prime_UTR_variant	6/6	ENST00000261751.8	NP_000741.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHRNB4	ENST00000412074.6	c.594T>A	p.Ala198Ala	synonymous_variant	5/5	1		ENSP00000416386.2
CHRNB4	ENST00000261751.8	c.*76T>A		3_prime_UTR_variant	6/6	1	NM_000750.5	ENSP00000261751.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 1457178 Hom.: 0 Cov.: 68 AF XY: 0.00 AC XY: 0 AN XY: 725044

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	0.85
DANN	Benign	0.63

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: rs1948; hg19: chr15-78917399;