18-33607606-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_030632.3(ASXL3):c.67C>T(p.His23Tyr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000315 in 1,585,976 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000028 (0 hom.)
• Consequence: ASXL3 NM_030632.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.08

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]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.02949202).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ASXL3	NM_030632.3	c.67C>T	p.His23Tyr	missense_variant	2/12	ENST00000269197.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ASXL3	ENST00000269197.12	c.67C>T	p.His23Tyr	missense_variant	2/12	5	NM_030632.3	P4

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 151900 Hom.: 0 Cov.: 32

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: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000955 AC: 2 AN: 209390 Hom.: 0 AF XY: 0.00000893 AC XY: 1 AN XY: 111946

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 SAS exome AF: 0.0000778

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000279 AC: 4 AN: 1433958 Hom.: 0 Cov.: 30 AF XY: 0.00000563 AC XY: 4 AN XY: 710614

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000367

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000168

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152018 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74320

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ExAC AF: 0.00000833 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Mar 06, 2024

Variant summary: ATM c.67C>T (p.Arg23X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 2e-05 in 251364 control chromosomes. c.67C>T has been reported in the literature in individuals affected with Ataxia-Telangiectasia. These data indicate that the variant is likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in <10% of normal activity. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Benign	-0.24	T
BayesDel_noAF	Benign	-0.58
Cadd	Benign	18
Dann	Benign	0.47
DEOGEN2	Benign	0.0058	T
Eigen	Benign	-0.66
Eigen_PC	Benign	-0.39
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Benign	0.74	T
M_CAP	Benign	0.0057	T
MetaRNN	Benign	0.029	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-1.4	N
MutationTaster	Benign	0.94	N
PrimateAI	Pathogenic	0.87	D
PROVEAN	Benign	1.6	N
REVEL	Benign	0.072
Sift	Benign	0.33	T
Sift4G	Benign	1.0	T
Polyphen		0.0020	B
Vest4		0.30
MutPred		0.17		Gain of catalytic residue at P27 (P = 0.0715);
MVP		0.10
MPC		0.55
ClinPred		0.16	T
GERP RS		4.8
Varity_R		0.098
gMVP		0.30

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

Publications

LitVar

Other links and lift over

dbSNP: rs555478574; hg19: chr18-31187570; COSMIC: COSV52463056;