6-51748086-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP5

The NM_138694.4(PKHD1):​c.9530T>C​(p.Ile3177Thr) variant causes a missense change. The variant allele was found at a frequency of 0.0000917 in 1,613,662 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000096 ( 0 hom. )

Consequence

PKHD1
NM_138694.4 missense

Scores

9
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:8U:3

Conservation

PhyloP100: 6.10
Variant links:
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]

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 6-51748086-A-G is Pathogenic according to our data. Variant chr6-51748086-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 377018.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=5, Uncertain_significance=2, Pathogenic=2}. Variant chr6-51748086-A-G is described in Lovd as [Pathogenic]. Variant chr6-51748086-A-G is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
PKHD1NM_138694.4 linkuse as main transcriptc.9530T>C p.Ile3177Thr missense_variant 58/67 ENST00000371117.8 NP_619639.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
PKHD1ENST00000371117.8 linkuse as main transcriptc.9530T>C p.Ile3177Thr missense_variant 58/671 NM_138694.4 ENSP00000360158 P2P08F94-1
PKHD1ENST00000340994.4 linkuse as main transcriptc.9530T>C p.Ile3177Thr missense_variant 58/615 ENSP00000341097 A2P08F94-2

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152216
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000518
AC:
13
AN:
250878
Hom.:
0
AF XY:
0.0000369
AC XY:
5
AN XY:
135538
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000115
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000965
AC:
141
AN:
1461446
Hom.:
0
Cov.:
33
AF XY:
0.0000825
AC XY:
60
AN XY:
727056
show subpopulations
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:
0.000125
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000460
AC:
7
AN:
152216
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74378
show subpopulations
Gnomad4 AFR
AF:
0.0000241
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:
0.0000882
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000807
Hom.:
0
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:8Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:4Uncertain:1
Likely pathogenic, criteria provided, single submitterclinical testingGeneDxMar 22, 2021Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 31980526, 30507656, 19940839, 30595564, 15698423, 12846734, 15108281, 18503009, 30650191, 16133180, 19914852, 15108277, 12874454) -
Pathogenic, criteria provided, single submitterclinical testingCenter for Pediatric Genomic Medicine, Children's Mercy Hospital and ClinicsJan 06, 2017- -
Uncertain significance, no assertion criteria providedresearchGharavi Laboratory, Columbia UniversitySep 16, 2018- -
Likely pathogenic, criteria provided, single submitterclinical testingMayo Clinic Laboratories, Mayo ClinicNov 25, 2019PM2, PM3, PP1, PP4, PP5 -
Pathogenic, no assertion criteria providedclinical testingDepartment of Pathology and Laboratory Medicine, Sinai Health System-The PKHD1 p.Ile3177Thr variant was identified in 10 of 974 proband chromosomes (frequency: 0.01) from individuals or families with ARPKD (Bergmann 2005, Denamur 2010, Furu 2004, Gunay-Aygun 2010, Losekoot 2005, Rosetti 2003).The variant was also identified in dbSNP (ID: rs200511261), Clinvitae database (as pathogenic by Emory genetics) RWTH AAachen University ARPKD database (as pathogenic) and PKHD1-LOVD. This variant was identified in the NHLBI GO Exome Sequencing Project in 1 of 8600 European American alleles (freq. 0.0001) and Exome Aggregation Consortium database (March 14, 2016) in 5 of 66720 chromosomes (freq. 7.49E-05) in the European population, this low number of observations and low frequency is not substantive enough to determine the prevalence of the variant in the general population and its relationship to disease. The p.Ile3177 residue is not conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. The variant occurs outside of the splicing consensus sequence and 1 of 5 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) predict a greater than 10% difference in splicing; this is not very predictive of pathogenicity. The case studies by Arbeiter (2008) and Denamur (2010) identify this mutation along with evolutionarily highly conserved missense change c.2414CT (p.Pro805Leu) in patients who died perinatally from ARPKD. In addition, several studies found the variant in patients with severe perinatally-fatal phenotype of ARPKD (Bergmann 2005, Furu 2004, Gunay-Aygun 2010, Rosetti 2003, Losekoot 2005). In summary, based on the above information, this variant meets our laboratory’s criteria to be classified as pathogenic. -
Autosomal recessive polycystic kidney disease Pathogenic:2Uncertain:1
Likely pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsOct 31, 2018- -
Pathogenic, criteria provided, single submitterclinical testingBaylor Genetics-- -
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 21, 2024This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 3177 of the PKHD1 protein (p.Ile3177Thr). This variant is present in population databases (rs200511261, gnomAD 0.01%). This missense change has been observed in individual(s) with polycystic kidney disease on the same chromosome with another PKHD1 variant (p.Pro805Leu)(PMID: 16133180, 15108281, 18503009, 19940839). The haplotype (Pro805Leu; Ile3177Thr) has been observed on the opposite chromosome from other pathogenic variants in an individuals affected with polycystic kidney disease (PMID: 12846734, 15108281, Invitae). ClinVar contains an entry for this variant (Variation ID: 377018). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on PKHD1 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Polycystic kidney disease 4 Pathogenic:2
Likely pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsFeb 24, 2024- -
Likely pathogenic, criteria provided, single submitterclinical testingJohns Hopkins Genomics, Johns Hopkins UniversityMar 10, 2021This PKHD1 variant (rs200511261) is rare (<0.1%) in a large population dataset (gnomAD: 13/250878 total alleles; 0.005%; no homozygotes) and has an entry in ClinVar. It has been observed on the opposite chromosome from other pathogenic variants in individuals affected with PKD4. Two bioinformatics tools queried predict that p.Ile3177Thr would be tolerated, while another predicts it would be damaging. The isoleucine residue at this position is partially conserved across the vertebrate species assessed; some species have a valine substitution at this position. This variant is not predicted to affect normal exon 58 splicing, although this has not been confirmed experimentally to our knowledge. We consider c.9530T>C to be likely pathogenic. -
PKHD1-related disorder Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingPreventionGenetics, part of Exact SciencesMar 13, 2023The PKHD1 c.9530T>C variant is predicted to result in the amino acid substitution p.Ile3177Thr. This variant has been reported in several patients with polycystic kidney disease. In the majority of patients, it was detected in combination with the PKHD1 variant c.2414C>T (p.Pro805Leu) (Rossetti et al. 2003. PubMed ID: 12846734; Shuster et al. 2019. PubMed ID: 30650191; Bergmann et al. 2004. PubMed ID: 15108281; Denamur et al. 2010. PubMed ID: 19940839; PreventionGenetics). In at least four of these patients familial testing confirmed these variants were inherited as a haplotype (in cis) on the same allele (c.[2414C>T;9530T>C] p.[Pro805Leu;Ile3177Thr]), and this haplotype was in trans with a second PKHD1 variant allele (Rossetti et al. 2003. PubMed ID: 12846734 ; Shuster. 2019. PubMed ID: 30650191; Bergmann et al. 2004. PubMed ID: 15108281). However, the c.9530T>C (p.Ile3177Thr) variant has also been reported in individuals with polycystic kidney disease without p.Pro805Leu (Rossetti et al. 2003. PubMed ID: 12846734; PreventionGenetics). In one case, it was shown to be in trans with the suspected pathogenic variant c.2269A>C (p.Ile757Leu) (Rossetti et al. 2003. PubMed ID: 12846734). The c.9530T>C (p.Ile3177Thr) variant is reported in 0.011% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/6-51612884-A-G). In conclusion, the haplotype c.[2414C>T;9530T>C] p.[Pro805Leu;Ile3177Thr] is considered to be pathogenic; however, the contribution of each variant is unknown. Although we suspect the c.9530T>C (p.Ile3177Thr) variant may be pathogenic, at this time the clinical significance of this variant is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.073
BayesDel_addAF
Uncertain
0.016
T
BayesDel_noAF
Uncertain
0.010
CADD
Benign
22
DANN
Uncertain
0.98
DEOGEN2
Benign
0.41
T;.
Eigen
Benign
0.075
Eigen_PC
Benign
0.19
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Benign
0.81
T;T
M_CAP
Uncertain
0.093
D
MetaRNN
Uncertain
0.53
D;D
MetaSVM
Benign
-0.55
T
MutationAssessor
Benign
1.8
L;L
MutationTaster
Benign
0.82
N;N
PrimateAI
Benign
0.33
T
PROVEAN
Benign
-2.2
N;N
REVEL
Uncertain
0.56
Sift
Uncertain
0.012
D;D
Sift4G
Uncertain
0.0040
D;D
Polyphen
0.28
B;B
Vest4
0.52
MVP
0.93
MPC
0.22
ClinPred
0.29
T
GERP RS
5.9
Varity_R
0.21
gMVP
0.51

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs200511261; hg19: chr6-51612884; API