rs797045101

Positions:

• chr6-51748056-GA-G

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_138694.4(PKHD1):​c.9559del​(p.Ser3187LeufsTer33) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,950 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: PKHD1 NM_138694.4 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 1.52

Genes affected

PKHD1 (HGNC:9016): (PKHD1 ciliary IPT domain containing fibrocystin/polyductin) The protein encoded by this gene is predicted to have a single transmembrane (TM)-spanning domain and multiple copies of an immunoglobulin-like plexin-transcription-factor domain. Alternative splicing results in two transcript variants encoding different isoforms. Other alternatively spliced transcripts have been described, but the full length sequences have not been determined. Several of these transcripts are predicted to encode truncated products which lack the TM and may be secreted. Mutations in this gene cause autosomal recessive polycystic kidney disease, also known as polycystic kidney and hepatic disease-1. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 18 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
• PP5: Variant 6-51748056-GA-G is Pathogenic according to our data. Variant chr6-51748056-GA-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 208604.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PKHD1	NM_138694.4	c.9559del	p.Ser3187LeufsTer33	frameshift_variant	58/67	ENST00000371117.8	NP_619639.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PKHD1	ENST00000371117.8	c.9559del	p.Ser3187LeufsTer33	frameshift_variant	58/67	1	NM_138694.4	ENSP00000360158	P2
PKHD1	ENST00000340994.4	c.9559del	p.Ser3187LeufsTer33	frameshift_variant	58/61	5		ENSP00000341097	A2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152166 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461784 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727192

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152166 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74328

Gnomad4 AFR AF: 0.00

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: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Autosomal recessive polycystic kidney disease Pathogenic:4

Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Dec 30, 2014	The p.Ser3187LeufsX33 variant in PKHD1 has not been previously reported in individuals with polycystic kidney disease and was absent from large population studies. This variant is predicted to cause a frameshift, which alters the protein’s amino acid sequence beginning at position 3187 and leads to a premature termination codon 33 amino acids downstream. This alteration is then predicted to lead to a truncated or absent protein. Complete loss of PKHD1 function is an established disease mechanism in polycystic kidney disease. In summary, this variant meets our criteria to be classified as pathogenic for polycystic kidney disease in an autosomal recessive manner (http://pcpgmwww.partners.org/personalizedmedicince/LMM) based upon the predicted impact of the variant. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Aug 21, 2022	For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 208604). This variant has not been reported in the literature in individuals affected with PKHD1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Ser3187Leufs*33) in the PKHD1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in PKHD1 are known to be pathogenic (PMID: 19940839). -
Likely pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Oct 27, 2021	Variant summary: PKHD1 c.9559delT (p.Ser3187LeufsX33) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. Additionally, trunctations in this gene have been associated with Polycystic Kidney And Hepatic Disease (Denamur_2010). The variant was absent in 250880 control chromosomes (gnomAD). c.9559delT has been reported in the literature in an individual affected with Polycystic Kidney And Hepatic Disease (Mansilla_2021). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and have classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 29, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics	Apr 10, 2015	- -

Polycystic kidney disease 4 Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 22, 2023	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Jul 11, 2023	- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs797045101; hg19: chr6-51612854;