chr12-112907038-CAAT-C

Variant names:

• chr12-112907038-CAAT-C
• rs1268296611
• NM_016816.4:c.-1_2delAAT

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_016816.4(OAS1):​c.-1_2delAAT​(p.Met1del) variant causes a start lost, conservative inframe deletion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,828 control chromosomes in the GnomAD database, with no homozygous occurrence. There is a variant allele frequency bias in the population database for this variant (GnomAdExome4), which may indicate mosaicism or somatic mutations in the reference population data. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: OAS1 NM_016816.4 start_lost, conservative_inframe_deletion
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.620
• Publications: 0 publications found

Genes affected

OAS1 (HGNC:8086): (2'-5'-oligoadenylate synthetase 1) This interferon-induced gene encodes a protein that synthesizes 2',5'-oligoadenylates (2-5As). This protein plays a key role in innate cellular antiviral response, and has been implicated in other cellular processes like cell growth and apoptosis. Alternative splicing results in multiple transcript variants with different enzymatic activities. Polymorphisms in this gene have been associated with susceptibility to viral infection, including SARS-CoV-2, and diabetes mellitus, type 1. This gene is located in a cluster of related genes on chromosome 12. [provided by RefSeq, May 2022]

OAS1 Gene-Disease associations (from GenCC):

• pulmonary alveolar proteinosis with hypogammaglobulinemia

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Start lost variant, no new inframe start found.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_016816.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	OAS1	NM_016816.4	MANE Select	c.-1_2delAAT	p.Met1del	start_lost conservative_inframe_deletion	Exon 1 of 6	NP_058132.2	P00973-1
	OAS1	NM_016816.4	MANE Select	c.-1_2delAAT		5_prime_UTR	Exon 1 of 6	NP_058132.2	P00973-1
	OAS1	NM_001032409.3		c.-1_2delAAT	p.Met1del	start_lost conservative_inframe_deletion	Exon 1 of 6	NP_001027581.1	P00973-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	OAS1	ENST00000202917.10	TSL:1 MANE Select	c.-1_2delAAT	p.Met1del	start_lost conservative_inframe_deletion	Exon 1 of 6	ENSP00000202917.5	P00973-1
	OAS1	ENST00000445409.7	TSL:1	c.-1_2delAAT	p.Met1del	start_lost conservative_inframe_deletion	Exon 1 of 6	ENSP00000388001.2	P00973-3
	OAS1	ENST00000540589.3	TSL:1	c.-1_2delAAT	p.Met1del	start_lost conservative_inframe_deletion	Exon 1 of 7	ENSP00000474083.2	S4R3A5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251336 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461828 Hom.: 0 AF XY: 0.00000550 AC XY: 4 AN XY: 727206

⚠️ 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: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86228

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000450 AC: 5 AN: 1111982

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00139817), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.62

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: rs1268296611; hg19: chr12-113344843;