chr16-2103822-A-C

Variant names:

• chr16-2103822-A-C
• rs556575921
• NM_001009944.3:c.8235T>G

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_Strong BP6_Very_Strong BP7

The NM_001009944.3(PKD1):​c.8235T>G​(p.Ser2745Ser) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000954 in 1,457,428 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00093 (1 hom., cov: 30)
  • Exomes 𝑓: 0.000095 (1 hom.)
  • Failed GnomAD Quality Control
• Consequence: PKD1 NM_001009944.3 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:6
• Conservation: PhyloP100: -4.73
• Publications: 0 publications found

Genes affected

PKD1 (HGNC:9008): (polycystin 1, transient receptor potential channel interacting) This gene encodes a member of the polycystin protein family. The encoded glycoprotein contains a large N-terminal extracellular region, multiple transmembrane domains and a cytoplasmic C-tail. It is an integral membrane protein that functions as a regulator of calcium permeable cation channels and intracellular calcium homoeostasis. It is also involved in cell-cell/matrix interactions and may modulate G-protein-coupled signal-transduction pathways. It plays a role in renal tubular development, and mutations in this gene cause autosomal dominant polycystic kidney disease type 1 (ADPKD1). ADPKD1 is characterized by the growth of fluid-filled cysts that replace normal renal tissue and result in end-stage renal failure. Splice variants encoding different isoforms have been noted for this gene. Also, six pseudogenes, closely linked in a known duplicated region on chromosome 16p, have been described. [provided by RefSeq, Oct 2008]

PKD1 Gene-Disease associations (from GenCC):

• autosomal dominant polycystic kidney disease

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• polycystic kidney disease 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• autosomal recessive polycystic kidney disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• Caroli disease

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp

ACMG classification

Our verdict: Benign. The variant received -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.97).
• BP6: Variant 16-2103822-A-C is Benign according to our data. Variant chr16-2103822-A-C is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 257016.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-4.73 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PKD1	NM_001009944.3	c.8235T>G	p.Ser2745Ser	synonymous_variant	Exon 23 of 46	ENST00000262304.9	NP_001009944.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PKD1	ENST00000262304.9	c.8235T>G	p.Ser2745Ser	synonymous_variant	Exon 23 of 46	1	NM_001009944.3	ENSP00000262304.4

Frequencies

GnomAD3 genomes AF: 0.000920 AC: 138 AN: 149972 Hom.: 1 Cov.: 30

Gnomad AFR AF: 0.00328

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000132

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000214

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000296

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.000198 AC: 49 AN: 246932 AF XY: 0.000156

Gnomad AFR exome AF: 0.00258

Gnomad AMR exome AF: 0.000145

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000551

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000181

Gnomad OTH exome AF: 0.000166

GnomAD4 exome AF: 0.0000954 AC: 139 AN: 1457428 Hom.: 1 Cov.: 34 AF XY: 0.0000841 AC XY: 61 AN XY: 725012

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00213 AC: 71 AN: 33304

American (AMR) AF: 0.000179 AC: 8 AN: 44690

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26124

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39694

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86144

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52040

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4138

European-Non Finnish (NFE) AF: 0.0000459 AC: 51 AN: 1111146

Other (OTH) AF: 0.000116 AC: 7 AN: 60148

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Data not reliable, filtered out with message: AS_VQSR AF: 0.000926 AC: 139 AN: 150094 Hom.: 1 Cov.: 30 AF XY: 0.000888 AC XY: 65 AN XY: 73228

African (AFR) AF: 0.00329 AC: 134 AN: 40668

American (AMR) AF: 0.000132 AC: 2 AN: 15160

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3454

East Asian (EAS) AF: 0.00 AC: 0 AN: 4924

South Asian (SAS) AF: 0.000214 AC: 1 AN: 4678

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10402

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 292

European-Non Finnish (NFE) AF: 0.0000296 AC: 2 AN: 67530

Other (OTH) AF: 0.00 AC: 0 AN: 2086

Alfa AF: 0.000324 Hom.: 0

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:2

Apr 25, 2025

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

-

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Polycystic kidney disease, adult type Benign:1

Jul 27, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Polycystic kidney disease Benign:1

-

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

The PKD1 p.Ser2745= variant was identified in 2 of 160 proband chromosomes (frequency: 0.0125) from individuals or families with ADPKD, and was not identified in 100 control chromosomes from healthy individuals (Watnick 1997). Affected individuals were discovered to have clusters of base pair substitutions in exons 23 and 25 in addition to the variant (c>8279T>C/M2760T, c>8282G>C/R2761P, c>8291T>C/M2764T c>8477T>C/I2826T, c>8287C>G/L2763V), and the variant segregated with disease in 1 kindred (Watnick 1997). In a study looking at the consequences of gene conversions in the PKD1 gene, pathogenicity was undetermined (Symmons 2008). The variant was also identified in dbSNP (ID: rs556575921) “With Likely benign allele”, ClinVar (classified likely benign by Prevention Genetics), LOVD 3.0 (1x), ADPKD Mutation Database (classified as highly likely pathogenic, exon 23 gene conversion (2)), and was not identified in COGR, and PKD1-LOVD databases. The variant was identified in control databases in 49 of 243470 chromosomes at a frequency of 0.0002 increasing the likelihood this could be a low frequency variant (Genome Aggregation Consortium Feb 27, 2017), being identified in the following populations: African in 39 of 14862 chromosomes (frequency: 0.003), Other in 1 of 5428 chromosomes (frequency: 0.0002), Latino in 6 of 33526 chromosomes (frequency: 0.0002), European Non-Finnish in 2 of 109758 chromosomes (frequency: 0.00002), and East Asian in 1 of 17192 chromosomes (frequency: 0.00006). In addition we cannot be certain that data from control databases is specific to PKD1 and not from one of the six PKD1 pseudogenes. The variant was identified in 1 individual with ADPKD in our laboratory, co-occurring with a pathogenic PKD2 variant (c.958C>T, p.Ala320X), increasing the likelihood the variant does not have clinical significance. The p.Ser2745= 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. -

Autosomal dominant polycystic kidney disease Benign:1

Jan 01, 2019

Molecular Genetics of Inherited Kidney Disorders Laboratory, Garvan Institute of Medical Research

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: research

- -

not provided Benign:1

Oct 02, 2020

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

See Variant Classification Assertion Criteria. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.97
CADD	Benign	0.17
DANN	Benign	0.29
PhyloP100		-4.7
Mutation Taster		=100/0	polymorphism

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

Other links and lift over

dbSNP: rs556575921; hg19: chr16-2153823;