chr10-49625563-G-C

Variant names:

• chr10-49625563-G-C
• rs768892260
• NM_020549.5:c.843G>C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP6_Moderate

The NM_020549.5(CHAT):​c.843G>C​(p.Arg281Arg) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000868 in 1,612,750 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000089 (0 hom.)
• Consequence: CHAT NM_020549.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.0700
• Publications: 0 publications found

Genes affected

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: STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• presynaptic congenital myasthenic syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• BP6: Variant 10-49625563-G-C is Benign according to our data. Variant chr10-49625563-G-C is described in ClinVar as Likely_benign. ClinVar VariationId is 461464.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020549.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHAT	NM_020549.5	MANE Select	c.843G>C	p.Arg281Arg	synonymous	Exon 6 of 15	NP_065574.4
	CHAT	NM_001142933.2		c.597G>C	p.Arg199Arg	synonymous	Exon 7 of 16	NP_001136405.2
	CHAT	NM_001142929.2		c.489G>C	p.Arg163Arg	synonymous	Exon 6 of 15	NP_001136401.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHAT	ENST00000337653.7	TSL:1 MANE Select	c.843G>C	p.Arg281Arg	synonymous	Exon 6 of 15	ENSP00000337103.2
	CHAT	ENST00000395562.2	TSL:1	c.597G>C	p.Arg199Arg	synonymous	Exon 7 of 16	ENSP00000378929.2
	CHAT	ENST00000339797.5	TSL:1	c.489G>C	p.Arg163Arg	synonymous	Exon 6 of 15	ENSP00000343486.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152162 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000161 AC: 4 AN: 248102 AF XY: 0.00000746

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000874

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000890

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000890 AC: 13 AN: 1460588 Hom.: 0 Cov.: 32 AF XY: 0.00000688 AC XY: 5 AN XY: 726444

African (AFR) AF: 0.00 AC: 0 AN: 33462

American (AMR) AF: 0.0000673 AC: 3 AN: 44608

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26090

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

South Asian (SAS) AF: 0.00 AC: 0 AN: 85808

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53284

Middle Eastern (MID) AF: 0.000349 AC: 2 AN: 5738

European-Non Finnish (NFE) AF: 0.00000450 AC: 5 AN: 1111574

Other (OTH) AF: 0.0000497 AC: 3 AN: 60344

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152162 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74320

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41440

American (AMR) AF: 0.00 AC: 0 AN: 15288

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68024

Other (OTH) AF: 0.00 AC: 0 AN: 2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000264

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial infantile myasthenia Benign:1

Nov 21, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.51
CADD	Benign	12
DANN	Benign	0.58
PhyloP100		-0.070

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.25		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.25		Position offset: 19

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs768892260; hg19: chr10-50833609;