chr6-52025518-C-A

Position:

• chr6-52025518-C-A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Moderate

The NM_138694.4(PKHD1):​c.4292G>T​(p.Cys1431Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. C1431S) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PKHD1 NM_138694.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.68

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 12 ACMG points.

• PM1: In a domain IPT/TIG 9 (size 92) in uniprot entity PKHD1_HUMAN there are 9 pathogenic changes around while only 0 benign (100%) in NM_138694.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr6-52025519-A-T is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991
• PP5: Variant 6-52025518-C-A is Pathogenic according to our data. Variant chr6-52025518-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1466642.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PKHD1	NM_138694.4	c.4292G>T	p.Cys1431Phe	missense_variant	32/67	ENST00000371117.8	NP_619639.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PKHD1	ENST00000371117.8	c.4292G>T	p.Cys1431Phe	missense_variant	32/67	1	NM_138694.4	ENSP00000360158	P2
PKHD1	ENST00000340994.4	c.4292G>T	p.Cys1431Phe	missense_variant	32/61	5		ENSP00000341097	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Autosomal recessive polycystic kidney disease Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 19, 2021

This sequence change replaces cysteine with phenylalanine at codon 1431 of the PKHD1 protein (p.Cys1431Phe). The cysteine residue is highly conserved and there is a large physicochemical difference between cysteine and phenylalanine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with PKHD1-related conditions. 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. This variant disrupts the p.Cys1431 amino acid residue in PKHD1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 27225849; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.79
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.25
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.90	D;.
Eigen	Uncertain	0.27
Eigen_PC	Benign	0.15
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.73	T;T
M_CAP	Pathogenic	0.31	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Uncertain	0.22	D
MutationAssessor	Pathogenic	3.0	M;M
MutationTaster	Benign	0.81	N;N
PrimateAI	Benign	0.38	T
PROVEAN	Pathogenic	-9.2	D;D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0040	D;D
Sift4G	Uncertain	0.0070	D;D
Polyphen		1.0	D;P
Vest4		0.84
MutPred		0.90		Gain of sheet (P = 0.0149);Gain of sheet (P = 0.0149);
MVP		0.98
MPC		0.45
ClinPred		1.0	D
GERP RS		5.0
Varity_R		0.96
gMVP		0.95

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr6-51890316;