chr20-25295207-C-T

Variant names:

• chr20-25295207-C-T
• rs2258719
• NM_002862.4:c.2313-397C>T

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BA1

The NM_002862.4(PYGB):​c.2313-397C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.383 in 152,174 control chromosomes in the GnomAD database, including 12,735 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency: Genomes: 𝑓 0.38 (12735 hom., cov: 34)
• Consequence: PYGB NM_002862.4 intron
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: -1.68
• Publications: 25 publications found

Genes affected

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]

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]

ABHD12 Gene-Disease associations (from GenCC):

• PHARC syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), PanelApp Australia, Orphanet, ClinGen

ACMG classification

Our verdict: Benign. The variant received -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.91).
• BP6: Variant 20-25295207-C-T is Benign according to our data. Variant chr20-25295207-C-T is described in ClinVar as Benign. ClinVar VariationId is 1244763.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BA1: GnomAd4 highest subpopulation (EAS) allele frequency at 95% confidence interval = 0.893 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PYGB	NM_002862.4	c.2313-397C>T		intron_variant	Intron 18 of 19	ENST00000216962.9	NP_002853.2
ABHD12	NM_015600.5	c.1158-177G>A		intron_variant	Intron 12 of 12		NP_056415.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PYGB	ENST00000216962.9	c.2313-397C>T		intron_variant	Intron 18 of 19	1	NM_002862.4	ENSP00000216962.3

Frequencies

GnomAD3 genomes AF: 0.383 AC: 58218 AN: 152052 Hom.: 12736 Cov.: 34

Gnomad AFR AF: 0.209

Gnomad AMI AF: 0.515

Gnomad AMR AF: 0.357

Gnomad ASJ AF: 0.316

Gnomad EAS AF: 0.915

Gnomad SAS AF: 0.451

Gnomad FIN AF: 0.451

Gnomad MID AF: 0.380

Gnomad NFE AF: 0.440

Gnomad OTH AF: 0.370

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.383 AC: 58229 AN: 152174 Hom.: 12735 Cov.: 34 AF XY: 0.387 AC XY: 28794 AN XY: 74400

African (AFR) AF: 0.209 AC: 8694 AN: 41520

American (AMR) AF: 0.356 AC: 5450 AN: 15292

Ashkenazi Jewish (ASJ) AF: 0.316 AC: 1095 AN: 3468

East Asian (EAS) AF: 0.915 AC: 4740 AN: 5180

South Asian (SAS) AF: 0.450 AC: 2172 AN: 4826

European-Finnish (FIN) AF: 0.451 AC: 4768 AN: 10578

Middle Eastern (MID) AF: 0.381 AC: 112 AN: 294

European-Non Finnish (NFE) AF: 0.440 AC: 29938 AN: 67988

Other (OTH) AF: 0.373 AC: 790 AN: 2116

Alfa AF: 0.395 Hom.: 15967

Bravo AF: 0.369

Asia WGS AF: 0.652 AC: 2265 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:2

-

Breakthrough Genomics, Breakthrough Genomics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: not provided

- -

Nov 10, 2018

GeneDx

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.91
CADD	Benign	0.027
DANN	Benign	0.46
PhyloP100		-1.7
Mutation Taster		=100/0	polymorphism (auto)

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: rs2258719; hg19: chr20-25275843;