6-52058438-C-G
Variant summary
Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM2PP3_ModeratePP5_Very_Strong
The NM_138694.4(PKHD1):c.1397G>C(p.Gly466Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000821 in 1,461,876 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G466E) has been classified as Likely benign.
Frequency
Consequence
NM_138694.4 missense
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Pathogenic. Variant got 12 ACMG points.
Transcripts
RefSeq
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
PKHD1 | ENST00000371117.8 | c.1397G>C | p.Gly466Ala | missense_variant | Exon 16 of 67 | 1 | NM_138694.4 | ENSP00000360158.3 | ||
PKHD1 | ENST00000340994.4 | c.1397G>C | p.Gly466Ala | missense_variant | Exon 16 of 61 | 5 | ENSP00000341097.4 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD3 exomes AF: 0.00000796 AC: 2AN: 251256Hom.: 0 AF XY: 0.00000736 AC XY: 1AN XY: 135782
GnomAD4 exome AF: 0.00000821 AC: 12AN: 1461876Hom.: 0 Cov.: 32 AF XY: 0.00000550 AC XY: 4AN XY: 727242
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
Autosomal recessive polycystic kidney disease Pathogenic:3Uncertain:1
- -
Variant summary: PKHD1 c.1397G>C (p.Gly466Ala) results in a non-conservative amino acid change located in the PA14/GLEYA domain (IPR037524) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 251256 control chromosomes (gnomAD). c.1397G>C has been reported in the literature in heterozygous state (i.e. without identifying a variant in trans) in 3 patients, from two families, where one of them was affected with predominant liver phenotype (Bergmann_2005). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. However, other missense changes affecting the same residue (G466E/R) have been reported in affected individuals (HGMD), and one of them (G466E) is classified as pathogenic by multiple reputable laboratories in ClinVar. The following publication has been ascertained in the context of this evaluation (PMID: 15698423). Two submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. One submitter classified the variant as likely pathogenic, and one submitter classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as likely pathogenic. -
- -
Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt PKHD1 protein function. ClinVar contains an entry for this variant (Variation ID: 551441). This missense change has been observed in individual(s) with polycystic kidney disease (PMID: 15698423). This variant is present in population databases (rs750730042, gnomAD 0.006%). This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 466 of the PKHD1 protein (p.Gly466Ala). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This variant disrupts the p.Gly466 amino acid residue in PKHD1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 20413436, 27225849, 27752906). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. -
Polycystic kidney disease 4 Pathogenic:3
- -
Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Likely pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with polycystic kidney disease 4, with or without hepatic disease (MIM#263200). (I) 0106 - This gene is associated with autosomal recessive disease; however, there are emerging reports of heterozygous carriers of PKHD1 variants developing liver cysts and nephrocalcinosis (PMID: 21945273). (I) 0115 - Variants in this gene are known to have variable expressivity. Significant intrafamilial variability has been reported (PMID: 20301501). (I) 0200 - Variant is predicted to result in a missense amino acid change from glycine to alanine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (2 heterozygotes, 0 homozygotes). (SP) 0309 - Multiple alternative amino acid changes at the same position have been observed in gnomAD (v3) (highest allele count: 3 heterozygotes, 0 homozygotes). (I) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (I) 0702 - Other missense variants comparable to the one identified in this case have strong previous evidence for pathogenicity. p.(Gly466Glu) has been classified as pathogenic or likely pathogenic by multiple clinical laboratories in ClinVar, and p.(Gly466Arg) has been observed as likely compound heterozygous in two individuals with polycystic kidney disease (PMIDs: 34536170, 29520754). (SP) 0808 - Previous reports of pathogenicity for this variant are conflicting. This variant has been classified as likely pathogenic or a VUS by clinical laboratories in ClinVar, and has been observed as a single heterozygous variant in two individuals with polycystic kidney disease (PMID: 15698423). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
- -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at