chr20-25295159-C-G

Position:

• chr20-25295159-C-G

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BA1

The NM_002862.4(PYGB):​c.2313-445C>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00539 in 948,530 control chromosomes in the GnomAD database, including 170 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.021 (99 hom., cov: 34)
  • Exomes 𝑓: 0.0025 (71 hom.)
• Consequence: PYGB NM_002862.4 intron
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: -0.806

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]

PYGB (HGNC:):

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP6: Variant 20-25295159-C-G is Benign according to our data. Variant chr20-25295159-C-G is described in ClinVar as [Benign]. Clinvar id is 1252428.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BA1: GnomAd4 highest subpopulation (AFR) allele frequency at 95% confidence interval = 0.0687 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PYGB	NM_002862.4	c.2313-445C>G		intron_variant		ENST00000216962.9	NP_002853.2
ABHD12	NM_015600.5	c.1158-129G>C		intron_variant			NP_056415.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PYGB	ENST00000216962.9	c.2313-445C>G		intron_variant		1	NM_002862.4	ENSP00000216962.3

Frequencies

GnomAD3 genomes AF: 0.0206 AC: 3138 AN: 152234 Hom.: 99 Cov.: 34

Gnomad AFR AF: 0.0709

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00857

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.000426

Gnomad OTH AF: 0.0167

GnomAD4 exome AF: 0.00248 AC: 1975 AN: 796178 Hom.: 71 AF XY: 0.00202 AC XY: 847 AN XY: 419468

Gnomad4 AFR exome AF: 0.0675

Gnomad4 AMR exome AF: 0.00478

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000200

Gnomad4 FIN exome AF: 0.0000831

Gnomad4 NFE exome AF: 0.000233

Gnomad4 OTH exome AF: 0.00619

GnomAD4 genome AF: 0.0206 AC: 3141 AN: 152352 Hom.: 99 Cov.: 34 AF XY: 0.0195 AC XY: 1450 AN XY: 74492

Gnomad4 AFR AF: 0.0708

Gnomad4 AMR AF: 0.00856

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000426

Gnomad4 OTH AF: 0.0166

Alfa AF: 0.0159 Hom.: 7

Bravo AF: 0.0240

Asia WGS AF: 0.00318 AC: 11 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:2

Benign, criteria provided, single submitter	clinical testing	GeneDx	Jan 25, 2019	- -
Benign, criteria provided, single submitter	not provided	Breakthrough Genomics, Breakthrough Genomics	-	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	2.6
DANN	Benign	0.68

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

Publications

LitVar

Other links and lift over

dbSNP: rs75097410; hg19: chr20-25275795;