1-231337382-C-A

Variant names:

• chr1-231337382-C-A
• rs1012596609
• NM_175876.5:c.364G>T

Variant summary

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

The NM_175876.5(EXOC8):​c.364G>T​(p.Glu122*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: EXOC8 NM_175876.5 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.88
• Publications: 0 publications found

Genes affected

EXOC8 (HGNC:24659): (exocyst complex component 8) This gene encodes a component of the exocyst complex, an evolutionarily conserved multi-protein complex that plays a critical role in vesicular trafficking and the secretory pathway by targeting post-Golgi vesicles to the plasma membrane. This protein is a target of activated Ral subfamily of GTPases and thereby regulates exocytosis by tethering vesicles to the plasma membrane. Mutations in this gene may be related to Joubert syndrome. [provided by RefSeq, Sep 2016]

SPRTN (HGNC:25356): (SprT-like N-terminal domain) The protein encoded by this gene may play a role in DNA repair during replication of damaged DNA. This protein recruits valosin containing protein (p97) to stalled DNA replication forks where it may prevent excessive translesional DNA synthesis and limit the number of DNA-damage induced mutations. It may also be involved in replication-related G2/M-checkpoint regulation. Deficiency of a similar protein in mouse causes chromosomal instability and progeroid phenotypes. Mutations in this gene have been associated with Ruijs-Aalfs syndrome (RJALS). Alternatively spliced transcript variants have been identified. [provided by RefSeq, Mar 2015]

SPRTN Gene-Disease associations (from GenCC):

• progeroid features-hepatocellular carcinoma predisposition syndrome

  Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), Orphanet, PanelApp Australia, G2P

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 is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.833 CDS is truncated, and there are 2 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_175876.5. 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
	EXOC8	NM_175876.5	MANE Select	c.364G>T	p.Glu122*	stop_gained	Exon 1 of 1	NP_787072.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	EXOC8	ENST00000366645.1	TSL:6 MANE Select	c.364G>T	p.Glu122*	stop_gained	Exon 1 of 1	ENSP00000355605.2	Q8IYI6
	SPRTN	ENST00000391858.8	TSL:1	c.-1002C>A		5_prime_UTR	Exon 1 of 4	ENSP00000375731.4	Q9H040-2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.42
FATHMM_MKL	Uncertain	0.88	D
PhyloP100		2.9
Vest4		0.22
GERP RS		4.2
PromoterAI		-0.072	Neutral
Mutation Taster		=12/188	disease causing

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: rs1012596609; hg19: chr1-231473128; COSMIC: COSV99150186; COSMIC: COSV99150186;