rs1057517665

Variant names:

• chr10-49611297-G-C
• rs1057517665
• NM_003055.3:c.557G>C
• SLC18A3 p.Gly186Ala

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_003055.3(SLC18A3):​c.557G>C​(p.Gly186Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,456,228 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: 35)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SLC18A3 NM_003055.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 9.67
• Publications: 4 publications found

Genes affected

SLC18A3 (HGNC:10936): (solute carrier family 18 member A3) This gene is a member of the vesicular amine transporter family. The encoded transmembrane protein transports acetylcholine into secretory vesicles for release into the extracellular space. Acetylcholine transport utilizes a proton gradient established by a vacuolar ATPase. This gene is located within the first intron of the choline acetyltransferase gene. [provided by RefSeq, Jul 2008]

CHAT (HGNC:1912): (choline O-acetyltransferase) This gene encodes an enzyme which catalyzes the biosynthesis of the neurotransmitter acetylcholine. This gene product is a characteristic feature of cholinergic neurons, and changes in these neurons may explain some of the symptoms of Alzheimer's disease. Polymorphisms in this gene have been associated with Alzheimer's disease and mild cognitive impairment. Mutations in this gene are associated with congenital myasthenic syndrome associated with episodic apnea. Multiple transcript variants encoding different isoforms have been found for this gene, and some of these variants have been shown to encode more than one isoform. [provided by RefSeq, May 2010]

CHAT Gene-Disease associations (from GenCC):

• congenital myasthenic syndrome 6

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp
• presynaptic congenital myasthenic syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003055.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SLC18A3	NM_003055.3	MANE Select	c.557G>C	p.Gly186Ala	missense	Exon 1 of 1	NP_003046.2	Q16572
	CHAT	NM_020984.4		c.-69+2098G>C		intron	N/A	NP_066264.4	P28329-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SLC18A3	ENST00000374115.5	TSL:6 MANE Select	c.557G>C	p.Gly186Ala	missense	Exon 1 of 1	ENSP00000363229.3	Q16572
	CHAT	ENST00000339797.5	TSL:1	c.-69+2098G>C		intron	N/A	ENSP00000343486.1	P28329-3

Frequencies

GnomAD3 genomes Cov.: 35

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1456228 Hom.: 0 Cov.: 80 AF XY: 0.00000138 AC XY: 1 AN XY: 724770

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44710

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26110

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 47980

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111892

Other (OTH) AF: 0.00 AC: 0 AN: 60350

GnomAD4 genome Cov.: 35

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	1	-	Congenital myasthenic syndrome 21 (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.80	D
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	0.49	D
MutationAssessor	Pathogenic	3.7	H
PhyloP100		9.7
PrimateAI	Pathogenic	0.83	D
PROVEAN	Pathogenic	-5.6	D
REVEL	Pathogenic	0.87
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Varity_R		0.94
gMVP		0.95
Mutation Taster		=2/98	disease causing

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs1057517665;

hg19: chr10-50819343;