chr17-58213871-T-A

Variant names:

• chr17-58213871-T-A
• rs773036963
• NM_017777.4:c.645-2A>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_017777.4(MKS1):​c.645-2A>T variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,340 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: MKS1 NM_017777.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.47
• Publications: 0 publications found

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]

MKS1 Gene-Disease associations (from GenCC):

• Meckel syndrome, type 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Myriad Women’s Health, Labcorp Genetics (formerly Invitae)
• Bardet-Biedl syndrome 13

  Inheritance: Unknown, AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, G2P
• Joubert syndrome 28

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• Bardet-Biedl syndrome

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Joubert syndrome with ocular defect

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.0625 fraction of the gene. Cryptic splice site detected, with MaxEntScore 9.6, offset of -39, new splice context is: ctcttcttgtttccctgaAGgac. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-58213871-T-A is Pathogenic according to our data. Variant chr17-58213871-T-A is described in ClinVar as Pathogenic. ClinVar VariationId is 571828.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_017777.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MKS1	NM_017777.4	MANE Select	c.645-2A>T		splice_acceptor intron	N/A	NP_060247.2
	MKS1	NM_001321269.2		c.645-2A>T		splice_acceptor intron	N/A	NP_001308198.1
	MKS1	NM_001330397.2		c.645-2A>T		splice_acceptor intron	N/A	NP_001317326.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MKS1	ENST00000393119.7	TSL:1 MANE Select	c.645-2A>T		splice_acceptor intron	N/A	ENSP00000376827.2
	MKS1	ENST00000537529.7	TSL:1	c.216-2A>T		splice_acceptor intron	N/A	ENSP00000442096.3
	MKS1	ENST00000679081.1		n.2659A>T		non_coding_transcript_exon	Exon 4 of 5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000401 AC: 1 AN: 249556 AF XY: 0.00

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459340 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 726208

African (AFR) AF: 0.00 AC: 0 AN: 33414

American (AMR) AF: 0.0000224 AC: 1 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39690

South Asian (SAS) AF: 0.00 AC: 0 AN: 86192

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1109730

Other (OTH) AF: 0.00 AC: 0 AN: 60300

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000827 AC: 1

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Meckel-Gruber syndrome;C0431399:Joubert syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		7.5
GERP RS		6.0
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.96		Position offset: 37
DS_AL_spliceai		1.0		Position offset: -2

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

Other links and lift over

dbSNP: rs773036963; hg19: chr17-56291232;