chr22-19963684-C-T

Variant names:

• chr22-19963684-C-T
• rs4818
• NM_000754.4:c.408C>T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_000754.4(COMT):​c.408C>T​(p.Leu136Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,520 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. L136L) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: COMT NM_000754.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.271
• Publications: 366 publications found

Genes affected

COMT (HGNC:2228): (catechol-O-methyltransferase) Catechol-O-methyltransferase catalyzes the transfer of a methyl group from S-adenosylmethionine to catecholamines, including the neurotransmitters dopamine, epinephrine, and norepinephrine. This O-methylation results in one of the major degradative pathways of the catecholamine transmitters. In addition to its role in the metabolism of endogenous substances, COMT is important in the metabolism of catechol drugs used in the treatment of hypertension, asthma, and Parkinson disease. COMT is found in two forms in tissues, a soluble form (S-COMT) and a membrane-bound form (MB-COMT). The differences between S-COMT and MB-COMT reside within the N-termini. Several transcript variants are formed through the use of alternative translation initiation sites and promoters. [provided by RefSeq, Sep 2008]

MIR4761 (HGNC:41591): (microRNA 4761) microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop. [provided by RefSeq, Sep 2009]

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.72).
• BP7: Synonymous conserved (PhyloP=0.271 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000754.4. 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
	COMT	NM_000754.4	MANE Select	c.408C>T	p.Leu136Leu	synonymous	Exon 4 of 6	NP_000745.1
	COMT	NM_001135161.2		c.408C>T	p.Leu136Leu	synonymous	Exon 4 of 6	NP_001128633.1
	COMT	NM_001135162.2		c.408C>T	p.Leu136Leu	synonymous	Exon 4 of 6	NP_001128634.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COMT	ENST00000361682.11	TSL:1 MANE Select	c.408C>T	p.Leu136Leu	synonymous	Exon 4 of 6	ENSP00000354511.6
	COMT	ENST00000406520.7	TSL:1	c.408C>T	p.Leu136Leu	synonymous	Exon 4 of 6	ENSP00000385150.3
	COMT	ENST00000449653.5	TSL:1	c.258C>T	p.Leu86Leu	synonymous	Exon 2 of 4	ENSP00000416778.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460520 Hom.: 0 Cov.: 58 AF XY: 0.00 AC XY: 0 AN XY: 726586

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44700

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52220

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111900

Other (OTH) AF: 0.00 AC: 0 AN: 60378

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.72
CADD	Benign	5.0
DANN	Benign	0.92
PhyloP100		0.27
RBP_binding_hub_radar		1.0
RBP_regulation_power_radar		2.1

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

Other links and lift over

dbSNP: rs4818; hg19: chr22-19951207;