20-32433408-C-T

Variant names:

• chr20-32433408-C-T
• rs373145711
• NM_015338.6:c.1210C>T

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1 PP5_Very_Strong

The NM_015338.6(ASXL1):​c.1210C>T​(p.Arg404*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000242 in 1,613,920 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. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000024 (0 hom.)
• Consequence: ASXL1 NM_015338.6 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 2.06
• Publications: 21 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: Illumina, Laboratory for Molecular Medicine, Orphanet, G2P, PanelApp Australia, ClinGen, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 16 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 20-32433408-C-T is Pathogenic according to our data. Variant chr20-32433408-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 30986.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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.1210C>T	p.Arg404*	stop_gained	Exon 12 of 13	NP_056153.2
	ASXL1	NM_001363734.1		c.1027C>T	p.Arg343*	stop_gained	Exon 11 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.1210C>T	p.Arg404*	stop_gained	Exon 12 of 13	ENSP00000364839.4	Q8IXJ9-1
	ASXL1	ENST00000306058.9	TSL:1	c.1195C>T	p.Arg399*	stop_gained	Exon 11 of 12	ENSP00000305119.5	Q76L82
	ASXL1	ENST00000905973.1		c.1207C>T	p.Arg403*	stop_gained	Exon 11 of 12	ENSP00000576032.1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152116 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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: 0.0000441

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000199 AC: 5 AN: 251442 AF XY: 0.0000221

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.0000992

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000462

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000239 AC: 35 AN: 1461804 Hom.: 0 Cov.: 31 AF XY: 0.0000371 AC XY: 27 AN XY: 727172

⚠️ 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: 0.0000383 AC: 1 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86258

European-Finnish (FIN) AF: 0.0000374 AC: 2 AN: 53408

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

European-Non Finnish (NFE) AF: 0.0000261 AC: 29 AN: 1111940

Other (OTH) AF: 0.0000331 AC: 2 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152116 Hom.: 0 Cov.: 32 AF XY: 0.0000404 AC XY: 3 AN XY: 74308

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

African (AFR) AF: 0.0000241 AC: 1 AN: 41420

American (AMR) AF: 0.00 AC: 0 AN: 15274

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10596

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000441 AC: 3 AN: 68022

Other (OTH) AF: 0.00 AC: 0 AN: 2090

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.0000761 Hom.: 0

ESP6500AA AF: 0.000454 AC: 2

ESP6500EA AF: 0.00 AC: 0

ExAC AF: 0.0000576 AC: 7

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
4	-	-	Bohring-Opitz syndrome (4)
1	-	-	Developmental delay;CN239855:dystrophia (1)
1	-	-	Hypertrichosis;C0036857:severe intellectual disability;C0232466:Feeding difficulties;C0235991:Small for gestational age;C0454644:Delayed speech and language development;C0557874:Global developmental delay;C1837658:Delayed gross motor development;C1842581:Abnormal corpus callosum morphology;C1854408:Glabellar hemangioma;C1857949:Prominent metopic ridge (1)
1	-	-	Myelodysplastic syndrome (1)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	37
DANN	Uncertain	0.99
Eigen	Uncertain	0.43
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Uncertain	0.86	D
PhyloP100		2.1
Vest4		0.93
GERP RS		3.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=1/199	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs373145711; hg19: chr20-31021211; COSMIC: COSV60102210; COSMIC: COSV60102210;