NM_017777.4:c.*70C>A

Variant names:

• chr17-58206009-G-T
• NM_017777.4:c.*70C>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_017777.4(MKS1):​c.*70C>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000285 in 1,401,574 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000029 (0 hom.)
• Consequence: MKS1 NM_017777.4 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.319
• 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_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.72).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MKS1	NM_017777.4	c.*70C>A		3_prime_UTR_variant	Exon 18 of 18	ENST00000393119.7	NP_060247.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MKS1	ENST00000393119.7	c.*70C>A		3_prime_UTR_variant	Exon 18 of 18	1	NM_017777.4	ENSP00000376827.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000285 AC: 4 AN: 1401574 Hom.: 0 Cov.: 32 AF XY: 0.00000289 AC XY: 2 AN XY: 692264

African (AFR) AF: 0.00 AC: 0 AN: 31842

American (AMR) AF: 0.00 AC: 0 AN: 36216

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25256

East Asian (EAS) AF: 0.00 AC: 0 AN: 36262

South Asian (SAS) AF: 0.00 AC: 0 AN: 80046

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 46512

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4114

European-Non Finnish (NFE) AF: 0.00000369 AC: 4 AN: 1083200

Other (OTH) AF: 0.00 AC: 0 AN: 58126

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

MKS1-related disorder Uncertain:1

Mar 22, 2023

PreventionGenetics, part of Exact Sciences

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The MKS1 c.1667C>A variant is predicted to result in the amino acid substitution p.Pro556His. To our knowledge, this variant has not been reported in the literature or in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.72
CADD	Benign	3.0
DANN	Benign	0.86
PhyloP100		0.32

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

hg19: chr17-56283370;