chr20-32436833-TG-T

Variant names:

• chr20-32436833-TG-T
• rs1555912897
• NM_015338.6:c.4127delG

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_015338.6(ASXL1):​c.4127delG​(p.Gly1376ValfsTer74) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,870 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ASXL1 NM_015338.6 frameshift
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.629
• Publications: 0 publications found

Genes affected

ASXL1 (HGNC:18318): (ASXL transcriptional regulator 1) This gene is similar to the Drosophila additional sex combs gene, which encodes a chromatin-binding protein required for normal determination of segment identity in the developing embryo. The protein is a member of the Polycomb group of proteins, which are necessary for the maintenance of stable repression of homeotic and other loci. The protein is thought to disrupt chromatin in localized areas, enhancing transcription of certain genes while repressing the transcription of other genes. The protein encoded by this gene functions as a ligand-dependent co-activator for retinoic acid receptor in cooperation with nuclear receptor coactivator 1. Mutations in this gene are associated with myelodysplastic syndromes and chronic myelomonocytic leukemia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2009]

ASXL1 Gene-Disease associations (from GenCC):

• Bohring-Opitz syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Orphanet, Laboratory for Molecular Medicine, G2P, Illumina

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 7 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_015338.6. 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
	ASXL1	NM_015338.6	MANE Select	c.4127delG	p.Gly1376ValfsTer74	frameshift	Exon 13 of 13	NP_056153.2
	ASXL1	NM_001363734.1		c.3944delG	p.Gly1315ValfsTer74	frameshift	Exon 12 of 12	NP_001350663.1	A0A2R8Y5U1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ASXL1	ENST00000375687.10	TSL:5 MANE Select	c.4127delG	p.Gly1376ValfsTer74	frameshift	Exon 13 of 13	ENSP00000364839.4	Q8IXJ9-1
	ASXL1	ENST00000306058.9	TSL:1	c.4112delG	p.Gly1371ValfsTer74	frameshift	Exon 12 of 12	ENSP00000305119.5	Q76L82
	ASXL1	ENST00000905973.1		c.4124delG	p.Gly1375ValfsTer74	frameshift	Exon 12 of 12	ENSP00000576032.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461870 Hom.: 0 Cov.: 41 AF XY: 0.00 AC XY: 0 AN XY: 727238

African (AFR) AF: 0.0000299 AC: 1 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: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53396

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112012

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

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		-0.63
Mutation Taster		=41/159	disease causing

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: rs1555912897; hg19: chr20-31024636; COSMIC: COSV60113494; COSMIC: COSV60113494;