rs1555742167

Variant names:

• chr18-33738851-C-CT
• rs1555742167
• NM_030632.3:c.1448dupT

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_030632.3(ASXL3):​c.1448dupT​(p.Thr484AsnfsTer5) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ASXL3 NM_030632.3 frameshift
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 2.02
• Publications: 2 publications found

Genes affected

ASXL3 (HGNC:29357): (ASXL transcriptional regulator 3) This gene encodes a protein containing a plant homeodomain (PHD) zinc finger domain that plays a role in the regulation of gene transcription. The encoded protein has been shown to negatively regulate lipogenesis by binding to and inhibiting the transcriptional activity of two nuclear hormone receptors, oxysterols receptor LXR-alpha (LXRalpha) and thyroid hormone receptor beta (TRbeta). The encoded protein may also inhibit histone deubiquitination. Mutations in this gene have been identified in human patients with Bainbridge-Ropers syndrome, which is characterized by feeding difficulties, developmental delay and other features. [provided by RefSeq, May 2017]

ASXL3 Gene-Disease associations (from GenCC):

• severe feeding difficulties-failure to thrive-microcephaly due to ASXL3 deficiency syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Illumina, Orphanet, G2P
• syndromic intellectual disability

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 18-33738851-C-CT is Pathogenic according to our data. Variant chr18-33738851-C-CT is described in ClinVar as Pathogenic. ClinVar VariationId is 522176.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_030632.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ASXL3	NM_030632.3	MANE Select	c.1448dupT	p.Thr484AsnfsTer5	frameshift	Exon 11 of 12	NP_085135.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ASXL3	ENST00000269197.12	TSL:5 MANE Select	c.1448dupT	p.Thr484AsnfsTer5	frameshift	Exon 11 of 12	ENSP00000269197.4
	ASXL3	ENST00000696964.1		c.1451dupT	p.Thr485AsnfsTer5	frameshift	Exon 12 of 13	ENSP00000513003.1
	ASXL3	ENST00000681521.1		c.1328dupT	p.Thr444AsnfsTer5	frameshift	Exon 10 of 11	ENSP00000506037.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Severe feeding difficulties-failure to thrive-microcephaly due to ASXL3 deficiency syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.0
Mutation Taster		=1/199	disease causing (ClinVar)

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: rs1555742167; hg19: chr18-31318815;