rs140033417

Positions:

• chr6-51855931-A-G

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_138694.4(PKHD1):​c.7873T>C​(p.Leu2625=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00157 in 1,614,068 control chromosomes in the GnomAD database, including 48 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00094 (1 hom., cov: 33)
  • Exomes 𝑓: 0.0016 (47 hom.)
• Consequence: PKHD1 NM_138694.4 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:7
• Conservation: PhyloP100: -0.0230

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 Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP6: Variant 6-51855931-A-G is Benign according to our data. Variant chr6-51855931-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 262415.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000939 (143/152332) while in subpopulation SAS AF= 0.0292 (141/4826). AF 95% confidence interval is 0.0253. There are 1 homozygotes in gnomad4. There are 115 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High Homozygotes in GnomAdExome4 at 47 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PKHD1	NM_138694.4	c.7873T>C	p.Leu2625=	synonymous_variant	49/67	ENST00000371117.8	NP_619639.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PKHD1	ENST00000371117.8	c.7873T>C	p.Leu2625=	synonymous_variant	49/67	1	NM_138694.4	ENSP00000360158	P2
PKHD1	ENST00000340994.4	c.7873T>C	p.Leu2625=	synonymous_variant	49/61	5		ENSP00000341097	A2

Frequencies

GnomAD3 genomes AF: 0.000939 AC: 143 AN: 152214 Hom.: 1 Cov.: 33

Gnomad AFR AF: 0.0000482

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.0292

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00344 AC: 864 AN: 251392 Hom.: 15 AF XY: 0.00465 AC XY: 632 AN XY: 135866

Gnomad AFR exome AF: 0.000123

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.0273

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000528

Gnomad OTH exome AF: 0.00261

GnomAD4 exome AF: 0.00164 AC: 2391 AN: 1461736 Hom.: 47 Cov.: 30 AF XY: 0.00234 AC XY: 1701 AN XY: 727184

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.0000447

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0262

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000540

Gnomad4 OTH exome AF: 0.00197

GnomAD4 genome AF: 0.000939 AC: 143 AN: 152332 Hom.: 1 Cov.: 33 AF XY: 0.00154 AC XY: 115 AN XY: 74494

Gnomad4 AFR AF: 0.0000481

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.0292

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000223 Hom.: 1

Bravo AF: 0.000147

Asia WGS AF: 0.00751 AC: 26 AN: 3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Autosomal recessive polycystic kidney disease Benign:3

Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Apr 27, 2017	This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -
Benign, no assertion criteria provided	clinical testing	Natera, Inc.	May 11, 2017	- -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 31, 2024	- -

not specified Benign:2

Likely benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -
Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Oct 12, 2018	Variant summary: PKHD1 c.7873T>C alters a non-conserved nucleotide resulting in a synonymous change. 5/5 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.0031 in 277116 control chromosomes, predominantly at a frequency of 0.027 within the South Asian subpopulation in the gnomAD database, including 14 homozygotes. The observed variant frequency within South Asian control individuals in the gnomAD database is approximately 4-folds higher than the estimated maximal expected allele frequency for a pathogenic variant in PKHD1 causing Polycystic Kidney and Hepatic Disease phenotype (0.0071), strongly suggesting that the variant is a benign polymorphism found primarily in populations of South Asian origin. To our knowledge, no occurrence of c.7873T>C in individuals affected with Polycystic Kidney and Hepatic Disease and no experimental evidence demonstrating its impact on protein function have been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as benign. -

Polycystic kidney disease Benign:1

Likely benign, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The PKHD1 p.Leu2625= variant was not identified in the literature nor was it identified in the LOVD 3.0 database. The variant was identified in dbSNP (ID: rs140033417) as "With Likely benign allele", ClinVar (1x likely benign), and the RWTH AAachen University ARPKD database. The variant was also identified in control databases in 867 of 277116 chromosomes (16 homozygous) at a frequency of 0.003 increasing the likelihood this could be a low frequency benign variant (Genome Aggregation Database Feb 27, 2017). Breakdown of the observations by population include African in 2 of 24026 chromosomes (freq: 0.00008), Other in 13 of 6464 chromosomes (freq: 0.002), Latino in 2 of 34418 chromosomes (freq: 0.00006), European in 8 of 126612 chromosomes (freq: 0.00006), East Asian in 1 of 18870 chromosomes (freq: 0.00005), and South Asian in 841 of 30782 chromosomes (freq: 0.03). The variant was not observed in the Ashkenazi Jewish or Finnish, populations. The p.Leu2625= variant is not expected to have clinical significance because it does not result in a change of amino acid and is not located in a known consensus splice site. In addition, in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) do not predict a difference in splicing. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more benign role for this variant. This variant is classified as likely benign. -

not provided Benign:1

Benign, criteria provided, single submitter

clinical testing

GeneDx

May 11, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	0.52
DANN	Benign	0.45

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

LitVar

Other links and lift over

dbSNP: rs140033417; hg19: chr6-51720729; COSMIC: COSV61886338;