20-25294992-A-G

Position:

• chr20-25294992-A-G

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_015600.5(ABHD12):​c.1196T>C​(p.Met399Thr) variant causes a missense 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. 13/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 34)
• Consequence: ABHD12 NM_015600.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.05

Genes affected

ABHD12 (HGNC:15868): (abhydrolase domain containing 12, lysophospholipase) This gene encodes an enzyme that catalyzes the hydrolysis of 2-arachidonoyl glycerol (2-AG), the main endocannabinoid lipid transmitter that acts on cannabinoid receptors, CB1 and CB2. The endocannabinoid system is involved in a wide range of physiological processes, including neurotransmission, mood, appetite, pain appreciation, addiction behavior, and inflammation. Mutations in this gene are associated with the neurodegenerative disease, PHARC (polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataract), resulting from an inborn error of endocannabinoid metabolism. Alternatively spliced transcript variants encoding different isoforms have been noted for this gene.[provided by RefSeq, Jan 2011]

PYGB (HGNC:9723): (glycogen phosphorylase B) The protein encoded by this gene is a glycogen phosphorylase found predominantly in the brain. The encoded protein forms homodimers which can associate into homotetramers, the enzymatically active form of glycogen phosphorylase. The activity of this enzyme is positively regulated by AMP and negatively regulated by ATP, ADP, and glucose-6-phosphate. This enzyme catalyzes the rate-determining step in glycogen degradation. [provided by RefSeq, Jul 2008]

PYGB (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.053198695).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PYGB	NM_002862.4	c.2313-612A>G		intron_variant		ENST00000216962.9	NP_002853.2
ABHD12	NM_015600.5	c.1196T>C	p.Met399Thr	missense_variant	13/13		NP_056415.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PYGB	ENST00000216962.9	c.2313-612A>G		intron_variant		1	NM_002862.4	ENSP00000216962.3

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 34

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

CeGaT Center for Human Genetics Tuebingen

Feb 01, 2023

ABHD12: PM2, BP4 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.39	T
BayesDel_noAF	Benign	-0.80
CADD	Benign	0.18
DANN	Benign	0.69
Eigen	Benign	-1.4
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.015	N
LIST_S2	Benign	0.26	T
M_CAP	Benign	0.0018	T
MetaRNN	Benign	0.053	T
MetaSVM	Benign	-0.99	T
PrimateAI	Benign	0.39	T
PROVEAN	Benign	-0.18	N
REVEL	Benign	0.0050
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		0.0	B
Vest4		0.18
MutPred		0.14		Gain of phosphorylation at M399 (P = 0.0191);
MVP		0.048
MPC		0.26
ClinPred		0.034	T
GERP RS		-5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
gMVP		0.49

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: chr20-25275628;