6-13278319-T-C

Position:

• chr6-13278319-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2 PP2 PP3_Moderate PP5_Moderate

The NM_030948.6(PHACTR1):​c.1499T>C​(p.Leu500Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PHACTR1 NM_030948.6 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 7.44

Genes affected

PHACTR1 (HGNC:20990): (phosphatase and actin regulator 1) The protein encoded by this gene is a member of the phosphatase and actin regulator family of proteins. This family member can bind actin and regulate the reorganization of the actin cytoskeleton. It plays a role in tubule formation and in endothelial cell survival. Polymorphisms in this gene are associated with susceptibility to myocardial infarction, coronary artery disease and cervical artery dissection. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Apr 2016]

TBC1D7-LOC100130357 (HGNC:):

TBC1D7 (HGNC:21066): (TBC1 domain family member 7) This gene encodes a member of the TBC-domain containing protein family. The encoded protein functions as a subunit of the tuberous sclerosis TSC1-TSC2 complex which plays a role in the regulation of cellular growth and differentiation. Mutations in this gene have been associated with autosomal recessive megalencephaly. Alternative splicing results in multiple transcript variants. Naturally occurring readthrough transcription occurs between this locus and downstream LOC100130357. [provided by RefSeq, Jan 2016]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), PHACTR1. . Gene score misZ 0.708 (greater than the threshold 3.09). Trascript score misZ 3.1944 (greater than threshold 3.09). GenCC has associacion of gene with West syndrome, developmental and epileptic encephalopathy, 70.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.848
• PP5: Variant 6-13278319-T-C is Pathogenic according to our data. Variant chr6-13278319-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 617491.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr6-13278319-T-C is described in UniProt as null. Variant chr6-13278319-T-C is described in UniProt as null. Variant chr6-13278319-T-C is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PHACTR1	NM_030948.6	c.1499T>C	p.Leu500Pro	missense_variant	12/15	ENST00000332995.12	NP_112210.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PHACTR1	ENST00000332995.12	c.1499T>C	p.Leu500Pro	missense_variant	12/15	2	NM_030948.6	ENSP00000329880.8

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1446850 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 718020

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Developmental and epileptic encephalopathy, 70 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	Jul 17, 2023	Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0104 - Dominant negative is a likely mechanism of disease in this gene and is associated with developmental and epileptic encephalopathy 70 (MIM#618298). Functional assays have demonstrated that missense variants co-electroporated with wildtype constructs into corticol neurons maintained neuronal migration defects. However, there is also evidence indicating increased PPI binding, suggestive of a gain of function mechanism (PMID: 30256902; PMID: 33463715). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from leucine to proline. (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0600 - Variant is located in the annotated fourth RPEL region (PMID: 30256902). (I) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0802 - This variant has moderate previous evidence of pathogenicity in unrelated individuals. This variant has been observed as de novo in an individual with infantile spasms and intellectual disability (PMID: 30256902). (SP) 0905 - No published segregation evidence has been identified for this variant. (I) 1002 - This variant has moderate functional evidence supporting abnormal protein function. Transfected COS7 cells have proven this variant results in reduced actin-binding activity (PMID: 30256902). (SP) 1203 - This variant has been shown to be de novo in the proband (parental status confirmed, by trio analysis). (SP) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
Pathogenic, no assertion criteria provided	literature only	OMIM	Nov 25, 2020	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.25
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.56	D;T;D
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Uncertain	0.92	D
M_CAP	Uncertain	0.15	D
MetaRNN	Pathogenic	0.85	D;D;D
MetaSVM	Uncertain	-0.22	T
MutationAssessor	Uncertain	2.6	M;.;.
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-6.7	D;D;D
REVEL	Pathogenic	0.72
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;.;.
Vest4		0.90
MutPred		0.69		Gain of glycosylation at L500 (P = 0.0065);.;.;
MVP		0.82
ClinPred		1.0	D
GERP RS		4.9
Varity_R		0.84
gMVP		0.98

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: rs1562114406; hg19: chr6-13278551;