20-58900136-A-T

Variant names:

• chr20-58900136-A-T
• rs13831
• ENST00000481768.6:n.*273A>T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The ENST00000481768.6(GNAS):​n.*273A>T variant causes a non coding transcript exon change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.0 (0 hom., cov: 30)
  • Exomes 𝑓: 0.0000072 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: GNAS ENST00000481768.6 non_coding_transcript_exon
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.42
• Publications: 42 publications found

Genes affected

GNAS (HGNC:4392): (GNAS complex locus) This locus has a highly complex imprinted expression pattern. It gives rise to maternally, paternally, and biallelically expressed transcripts that are derived from four alternative promoters and 5' exons. Some transcripts contain a differentially methylated region (DMR) at their 5' exons, and this DMR is commonly found in imprinted genes and correlates with transcript expression. An antisense transcript is produced from an overlapping locus on the opposite strand. One of the transcripts produced from this locus, and the antisense transcript, are paternally expressed noncoding RNAs, and may regulate imprinting in this region. In addition, one of the transcripts contains a second overlapping ORF, which encodes a structurally unrelated protein - Alex. Alternative splicing of downstream exons is also observed, which results in different forms of the stimulatory G-protein alpha subunit, a key element of the classical signal transduction pathway linking receptor-ligand interactions with the activation of adenylyl cyclase and a variety of cellular reponses. Multiple transcript variants encoding different isoforms have been found for this gene. Mutations in this gene result in pseudohypoparathyroidism type 1a, pseudohypoparathyroidism type 1b, Albright hereditary osteodystrophy, pseudopseudohypoparathyroidism, McCune-Albright syndrome, progressive osseus heteroplasia, polyostotic fibrous dysplasia of bone, and some pituitary tumors. [provided by RefSeq, Aug 2012]

GNAS Gene-Disease associations (from GenCC):

• McCune-Albright syndrome

  Inheritance: AD, Unknown Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
• progressive osseous heteroplasia

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE, NO_KNOWN Submitted by: G2P, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• pseudohypoparathyroidism type 1B

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, Orphanet
• pseudohypoparathyroidism type 1C

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, Orphanet
• pseudopseudohypoparathyroidism

  Inheritance: AD, Mitochondrial Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Orphanet
• pseudohypoparathyroidism type 1A

  Inheritance: Mitochondrial, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.91).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GNAS	NM_080425.4	c.2186+1151A>T		intron_variant	Intron 3 of 12	ENST00000371100.9	NP_536350.2
GNAS	NM_000516.7	c.257+1151A>T		intron_variant	Intron 3 of 12	ENST00000371085.8	NP_000507.1
GNAS	NM_016592.5	c.*160+1151A>T		intron_variant	Intron 3 of 12	ENST00000371075.7	NP_057676.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GNAS	ENST00000371100.9	c.2186+1151A>T		intron_variant	Intron 3 of 12	5	NM_080425.4	ENSP00000360141.3
GNAS	ENST00000371085.8	c.257+1151A>T		intron_variant	Intron 3 of 12	1	NM_000516.7	ENSP00000360126.3
GNAS	ENST00000371075.7	c.*160+1151A>T		intron_variant	Intron 3 of 12	1	NM_016592.5	ENSP00000360115.3
GNAS	ENST00000676826.2	c.2186+1151A>T		intron_variant	Intron 3 of 12			ENSP00000504675.2
GNAS	ENST00000371102.8	c.2142-3392A>T		intron_variant	Intron 2 of 11	5		ENSP00000360143.4
GNAS	ENST00000354359.12	c.257+1151A>T		intron_variant	Intron 3 of 12	1		ENSP00000346328.7
GNAS	ENST00000371095.7	c.213-3392A>T		intron_variant	Intron 2 of 11	1		ENSP00000360136.3
GNAS	ENST00000470512.6	c.80+1151A>T		intron_variant	Intron 3 of 12	5		ENSP00000499552.2
GNAS	ENST00000480232.6	c.80+1151A>T		intron_variant	Intron 4 of 13	5		ENSP00000499545.2
GNAS	ENST00000663479.2	c.80+1151A>T		intron_variant	Intron 3 of 12			ENSP00000499353.2
GNAS	ENST00000462499.6	c.36-3392A>T		intron_variant	Intron 2 of 11	2		ENSP00000499758.2
GNAS	ENST00000467227.6	c.36-3392A>T		intron_variant	Intron 3 of 12	3		ENSP00000499681.2
GNAS	ENST00000478585.6	c.36-3392A>T		intron_variant	Intron 2 of 11	2		ENSP00000499762.2
GNAS	ENST00000481039.6	c.36-3392A>T		intron_variant	Intron 2 of 11	5		ENSP00000499767.2
GNAS	ENST00000485673.6	c.36-3392A>T		intron_variant	Intron 2 of 11	5		ENSP00000499334.2
GNAS	ENST00000488546.6	c.36-3392A>T		intron_variant	Intron 2 of 11	5		ENSP00000499332.2
GNAS	ENST00000492907.6	c.36-3392A>T		intron_variant	Intron 2 of 11	3		ENSP00000499443.2
GNAS	ENST00000461152.6	c.*125-3392A>T		intron_variant	Intron 2 of 2	5		ENSP00000499274.1
GNAS	ENST00000453292.7	c.*116-3392A>T		intron_variant	Intron 2 of 11	5		ENSP00000392000.2

Frequencies

GnomAD3 genomes AF: 0.00 AC: 0 AN: 151914 Hom.: 0 Cov.: 30

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000716 AC: 3 AN: 419016 Hom.: 0 Cov.: 0 AF XY: 0.0000135 AC XY: 3 AN XY: 221588

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

African (AFR) AF: 0.00 AC: 0 AN: 11204

American (AMR) AF: 0.00 AC: 0 AN: 15812

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 12932

East Asian (EAS) AF: 0.00 AC: 0 AN: 28940

South Asian (SAS) AF: 0.00 AC: 0 AN: 40328

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 30854

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 2080

European-Non Finnish (NFE) AF: 0.0000119 AC: 3 AN: 252344

Other (OTH) AF: 0.00 AC: 0 AN: 24522

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0225104), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 151914 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 74188

African (AFR) AF: 0.00 AC: 0 AN: 41360

American (AMR) AF: 0.00 AC: 0 AN: 15254

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5176

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10544

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 67972

Other (OTH) AF: 0.00 AC: 0 AN: 2088

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.91
CADD	Benign	0.16
DANN	Benign	0.67
PhyloP100		-1.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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: rs13831; hg19: chr20-57475191;