rs776060304
Variant summary
Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM2PP5_Very_Strong
The NM_138694.4(PKHD1):c.6900C>T(p.Asn2300Asn) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000236 in 1,610,438 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 Likely pathogenic (★★).
Frequency
Consequence
NM_138694.4 synonymous
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Pathogenic. Variant got 10 ACMG points.
Transcripts
RefSeq
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
PKHD1 | ENST00000371117.8 | c.6900C>T | p.Asn2300Asn | synonymous_variant | Exon 43 of 67 | 1 | NM_138694.4 | ENSP00000360158.3 | ||
PKHD1 | ENST00000340994.4 | c.6900C>T | p.Asn2300Asn | synonymous_variant | Exon 43 of 61 | 5 | ENSP00000341097.4 |
Frequencies
GnomAD3 genomes AF: 0.0000395 AC: 6AN: 151890Hom.: 0 Cov.: 31
GnomAD3 exomes AF: 0.0000159 AC: 4AN: 251312Hom.: 0 AF XY: 0.0000147 AC XY: 2AN XY: 135818
GnomAD4 exome AF: 0.0000219 AC: 32AN: 1458548Hom.: 0 Cov.: 29 AF XY: 0.0000207 AC XY: 15AN XY: 725802
GnomAD4 genome AF: 0.0000395 AC: 6AN: 151890Hom.: 0 Cov.: 31 AF XY: 0.0000270 AC XY: 2AN XY: 74152
ClinVar
Submissions by phenotype
Autosomal recessive polycystic kidney disease Pathogenic:2Uncertain:1
This sequence change affects codon 2300 of the PKHD1 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the PKHD1 protein. RNA analysis indicates that this variant induces altered splicing and may result in an absent or disrupted protein product. This variant is present in population databases (rs776060304, gnomAD 0.004%). This variant has been observed in individual(s) with polycystic kidney disease (PMID: 15698423, 15805161, 28170084; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 558073). Studies have shown that this variant results in aberrant mRNA splicing and introduces a premature termination codon (PMID: 28170084). The resulting mRNA is expected to undergo nonsense-mediated decay. For these reasons, this variant has been classified as Pathogenic. -
Variant summary: PKHD1 c.6900C>T alters a conserved nucleotide resulting in a synonymous change. Several computational tools predict a significant impact on normal splicing: Two predict the variant strengthens a cryptic 3' acceptor site. One study reported the variant resulted in the skipping of 47 nucleotides of exon 43 resulting in a reading frame shift (Balci_2017), while a second study reported that while this alternate splicing of exon 43 occurs at a basal level in control cells, it is promoted by the synonymous change shifting the expression ratio in favour of a shorter, out-of-frame transcript (Molinari_2020). The variant allele was found at a frequency of 1.6e-05 in 251312 control chromosomes. c.6900C>T has been reported in the literature in multiple individuals affected with Polycystic Kidney And Hepatic Disease in the compound heterozygous and homozygous state (Balci_2017, Molinari_2020, Burgmaier_2021). These data indicate that the variant is likely to be associated with disease. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One submitter classified the variant as likely pathogenic while two classified the variant as VUS. Based on the evidence outlined above, the variant was classified as likely pathogenic. -
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Polycystic kidney disease 4 Pathogenic:2
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not provided Pathogenic:1
Published functional studies suggest an aberrant splice effect, resulting in a shorter, out-of-frame transcript (PMID: 28170084, 33059616); In silico analysis is inconclusive as to whether the variant alters gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown.; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 15698423, 15805161, 33059616, 28170084, 33940108) -
PKHD1-related disorder Pathogenic:1
The PKHD1 c.6900C>T is a noncoding alteration. This variant has been reported in the homozygous and compound heterozygous state in individuals with PKHD1-related disease (Balci et al. 2017. PubMed ID: 28170084; Table S3, Burgmaier et al. 2021. PubMed ID: 33940108). The c.6900C site has been reported to be an exonic splicing enhancer and the C to T change caused aberrant mRNA splicing (a 47-nucleotide loss), resulting in a frameshift and premature protein termination (Balci et al. 2017. PubMed ID: 28170084; Molinari et al. 2020. PubMed ID: 33059616). This variant is reported in 0.0040% of alleles in individuals of African descent in gnomAD. This variant is interpreted as pathogenic. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at