19-12838580-ACT-A

Variant names:

• chr19-12838580-ACT-A
• rs1969787826
• NM_014975.3:c.15_16delCT

Variant summary

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

The NM_014975.3(MAST1):​c.15_16delCT​(p.Trp6AspfsTer5) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000126 in 1,581,944 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. L5L) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000067 (0 hom., cov: 31)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: MAST1 NM_014975.3 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.41
• Publications: 0 publications found

Genes affected

MAST1 (HGNC:19034): (microtubule associated serine/threonine kinase 1) This gene is a member of the microtubule-associated serine/threonine kinase (MAST) family. The protein encoded by this gene has an N-terminal serine/threonine kinase domain followed by a postsynaptic density protein-95/discs large/zona occludens-1 (PDZ) domain. In mouse and rat, the orthologous protein associates with the cytoskeleton and can bind both beta-2-syntrophin and neuronal nitric oxide synthase (nNOS) through its PDZ domain. In mouse and rat, this protein also co-localizes with dystrophin- and utrophin-associated protein complexes (DAPC/UAPC) in the vascular endothelium of the central nervous system. [provided by RefSeq, May 2017]

HOOK2 (HGNC:19885): (hook microtubule tethering protein 2) Hook proteins are cytosolic coiled-coil proteins that contain conserved N-terminal domains, which attach to microtubules, and more divergent C-terminal domains, which mediate binding to organelles. The Drosophila Hook protein is a component of the endocytic compartment.[supplied by OMIM, Apr 2004]

RTBDN (HGNC:30310): (retbindin) This gene was first identified in a study of human eye tissues. The protein encoded by this gene is preferentially expressed in the retina and may play a role in binding retinoids and other carotenoids as it shares homology with riboflavin binding proteins. Alternative splicing results in multiple transcript variants and protein isoforms. [provided by RefSeq, Jul 2012]

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 located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 17 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_014975.3. 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
	MAST1	NM_014975.3	MANE Select	c.15_16delCT	p.Trp6AspfsTer5	frameshift	Exon 1 of 26	NP_055790.1	Q9Y2H9

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MAST1	ENST00000251472.9	TSL:1 MANE Select	c.15_16delCT	p.Trp6AspfsTer5	frameshift	Exon 1 of 26	ENSP00000251472.3	Q9Y2H9
	MAST1	ENST00000591495.6	TSL:5	c.71+287_71+288delCT		intron	N/A	ENSP00000466470.1	K7EME4
	MAST1	ENST00000590883.1	TSL:5	n.115_116delCT		non_coding_transcript_exon	Exon 1 of 6

Frequencies

GnomAD3 genomes AF: 0.00000668 AC: 1 AN: 149616 Hom.: 0 Cov.: 31

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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000149

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 6.98e-7 AC: 1 AN: 1432328 Hom.: 0 AF XY: 0.00000140 AC XY: 1 AN XY: 712748

African (AFR) AF: 0.00 AC: 0 AN: 30406

American (AMR) AF: 0.00 AC: 0 AN: 42120

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25256

East Asian (EAS) AF: 0.00 AC: 0 AN: 35688

South Asian (SAS) AF: 0.00 AC: 0 AN: 83150

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51738

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5666

European-Non Finnish (NFE) AF: 9.10e-7 AC: 1 AN: 1099158

Other (OTH) AF: 0.00 AC: 0 AN: 59146

GnomAD4 genome AF: 0.00000668 AC: 1 AN: 149616 Hom.: 0 Cov.: 31 AF XY: 0.0000137 AC XY: 1 AN XY: 72910

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

African (AFR) AF: 0.00 AC: 0 AN: 40522

American (AMR) AF: 0.00 AC: 0 AN: 15088

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3452

East Asian (EAS) AF: 0.00 AC: 0 AN: 5074

South Asian (SAS) AF: 0.00 AC: 0 AN: 4660

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10310

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.0000149 AC: 1 AN: 67238

Other (OTH) AF: 0.00 AC: 0 AN: 2060

⚠️ 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: 0.00 Hom.: 0

Bravo AF: 0.00000378

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		2.4
Mutation Taster		=17/183	disease causing (fs/PTC)

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: rs1969787826; hg19: chr19-12949394; COSMIC: COSV52245656; COSMIC: COSV52245656;