NM_153704.6:c.869G>A

Variant names:

• chr8-93780747-G-A
• rs267607117
• NM_153704.6:c.869G>A

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1 PM2 PP3_Strong PP5_Moderate

The NM_153704.6(TMEM67):​c.869G>A​(p.Trp290*) variant causes a stop gained, splice region 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TMEM67 NM_153704.6 stop_gained, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.27
• Publications: 0 publications found

Genes affected

TMEM67 (HGNC:28396): (transmembrane protein 67) The protein encoded by this gene localizes to the primary cilium and to the plasma membrane. The gene functions in centriole migration to the apical membrane and formation of the primary cilium. Multiple transcript variants encoding different isoforms have been found for this gene. Defects in this gene are a cause of Meckel syndrome type 3 (MKS3) and Joubert syndrome type 6 (JBTS6). [provided by RefSeq, Nov 2008]

TMEM67 Gene-Disease associations (from GenCC):

• ciliopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• COACH syndrome 1

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• Meckel syndrome, type 3

  Inheritance: AR Classification: DEFINITIVE Submitted by: Ambry Genetics
• nephronophthisis 11

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• COACH syndrome 1

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics
• Joubert syndrome 6

  Inheritance: AR Classification: STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Joubert syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Meckel syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Senior-Boichis syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 16 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
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 8-93780747-G-A is Pathogenic according to our data. Variant chr8-93780747-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 2929045.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TMEM67	NM_153704.6	c.869G>A	p.Trp290*	stop_gained, splice_region_variant	Exon 8 of 28	ENST00000453321.8	NP_714915.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TMEM67	ENST00000453321.8	c.869G>A	p.Trp290*	stop_gained, splice_region_variant	Exon 8 of 28	1	NM_153704.6	ENSP00000389998.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Meckel-Gruber syndrome;C0431399:Joubert syndrome Pathogenic:1

Nov 19, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Trp290*) in the TMEM67 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in TMEM67 are known to be pathogenic (PMID: 20232449, 23559409). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TMEM67-related conditions. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	49
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		9.3
Vest4		0.90, 0.84
GERP RS		5.8
Mutation Taster		=2/198	disease causing (fs/PTC)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.67		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.67		Position offset: 0

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs267607117; hg19: chr8-94792975; COSMIC: COSV104404221; COSMIC: COSV104404221;