rs754279998

Variant names:

• chr17-58208152-TAGG-T
• rs754279998
• NM_017777.4:c.1115_1117delCCT

Variant summary

Our verdict is Pathogenic. Variant got 13 ACMG points: 13P and 0B. PM1 PM2 PM4_Supporting PP5_Very_Strong

The NM_017777.4(MKS1):​c.1115_1117delCCT​(p.Ser372del) variant causes a disruptive inframe deletion change. The variant allele was found at a frequency of 0.0000217 in 1,613,288 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000022 (0 hom.)
• Consequence: MKS1 NM_017777.4 disruptive_inframe_deletion
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:11 O:1
• Conservation: PhyloP100: 4.10

Genes affected

MKS1 (HGNC:7121): (MKS transition zone complex subunit 1) The protein encoded by this gene localizes to the basal body and is required for formation of the primary cilium in ciliated epithelial cells. Mutations in this gene result in Meckel syndrome type 1 and in Bardet-Biedl syndrome type 13. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2009]

ACMG classification

Verdict is Pathogenic. Variant got 13 ACMG points.

• PM1: In a domain C2 B9-type (size 128) in uniprot entity MKS1_HUMAN there are 9 pathogenic changes around while only 2 benign (82%) in NM_017777.4
• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_017777.4. Strenght limited to Supporting due to length of the change: 1aa.
• PP5: Variant 17-58208152-TAGG-T is Pathogenic according to our data. Variant chr17-58208152-TAGG-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 217677.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-58208152-TAGG-T is described in Lovd as [Pathogenic]. Variant chr17-58208152-TAGG-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MKS1	NM_017777.4	c.1115_1117delCCT	p.Ser372del	disruptive_inframe_deletion	Exon 13 of 18	ENST00000393119.7	NP_060247.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MKS1	ENST00000393119.7	c.1115_1117delCCT	p.Ser372del	disruptive_inframe_deletion	Exon 13 of 18	1	NM_017777.4	ENSP00000376827.2

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 151956 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000242

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000200 AC: 5 AN: 249558 Hom.: 0 AF XY: 0.0000148 AC XY: 2 AN XY: 135394

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000265

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000219 AC: 32 AN: 1461332 Hom.: 0 AF XY: 0.0000234 AC XY: 17 AN XY: 727020

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000225

Gnomad4 OTH exome AF: 0.0000497

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 151956 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74218

Gnomad4 AFR AF: 0.0000242

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000868 Hom.: 0

Bravo AF: 0.0000227

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:11 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Joubert syndrome 28 Pathogenic:2 Other:1

Pathogenic, no assertion criteria provided	research	Gene Discovery Core-Manton Center, Boston Children's Hospital	Feb 14, 2020	This variant is interpreted as Pathogenic for Joubert syndrome; Autosomal Recessive. PM1- Located in a mutational hot spot and/or critical and well-established functional domain (e.g., active site of an enzyme) without benign variation. PM2- Absent from controls or at extremely low frequency if recessive (0 homozygotes in gnomad). PM4- Protein length changes as a result of in-frame deletions/insertions in a non-repeat region or stop-loss variants. PP3- Multiple lines of computational evidence support a deleterious effect on the gene or gene product (conservation, evolutionary, splicing impact, etc.). PP5: Reputable source recently reports variant as pathogenic, but the evidence is not available to the laboratory to perform an independent evaluation, 6 nonconflicting ClinVar entries, (PMIDs: 24886560, 26092869, 26490104 and 27570071). -
Pathogenic, no assertion criteria provided	literature only	OMIM	Sep 23, 2016	- -
not provided, no classification provided	literature only	GeneReviews	-	- -

Meckel syndrome, type 1 Pathogenic:2

Likely pathogenic, criteria provided, single submitter	curation	Laboratory of Medical Genetics, National & Kapodistrian University of Athens	Feb 01, 2024	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -

Bardet-Biedl syndrome 13 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Centre for Mendelian Genomics, University Medical Centre Ljubljana	Jan 01, 2016	This variant was classified as: Pathogenic. This variant was detected in homozygous state. -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Dec 27, 2023	- -

Bardet-Biedl syndrome 13;C3714506:Meckel syndrome, type 1;C4310705:Joubert syndrome 28 Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Feb 03, 2017	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Mar 08, 2024	- -

Meckel-Gruber syndrome;C0431399:Familial aplasia of the vermis Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 12, 2025

This variant, c.1115_1117del, results in the deletion of 1 amino acid(s) of the MKS1 protein (p.Ser372del), but otherwise preserves the integrity of the reading frame. This variant is present in population databases (rs754279998, gnomAD 0.003%). This variant has been observed in individual(s) with Joubert syndrome (PMID: 24886560, 26092869, 27570071). This variant is also known as c.1085_1088delCCT (p.S362del). ClinVar contains an entry for this variant (Variation ID: 217677). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. For these reasons, this variant has been classified as Pathogenic. -

Polydactyly;C0239399:Limb undergrowth;C0240595:Rotary nystagmus;C0557874:Global developmental delay;C1561643:Chronic kidney disease Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Oct 23, 2015

- -

Familial aplasia of the vermis Pathogenic:1

Pathogenic, criteria provided, single submitter

research

UW Hindbrain Malformation Research Program, University of Washington

Feb 23, 2015

- -

Computational scores

Source: dbNSFP v4.3

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: rs754279998; hg19: chr17-56285513;