2-110123964-C-G

Position:

chr2-110123964-C-G

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2BP4_StrongBS1_Supporting

The NM_001128178.3(NPHP1):c.1861G>C(p.Glu621Gln) variant causes a missense change. The variant allele was found at a frequency of 0.000116 in 1,614,042 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E621D) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

NPHP1
NM_001128178.3 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 5.40

Variant links:

Genes affected

NPHP1 (HGNC:7905): (nephrocystin 1) This gene encodes a protein with src homology domain 3 (SH3) patterns. This protein interacts with Crk-associated substrate, and it appears to function in the control of cell division, as well as in cell-cell and cell-matrix adhesion signaling, likely as part of a multifunctional complex localized in actin- and microtubule-based structures. Mutations in this gene cause familial juvenile nephronophthisis type 1, a kidney disorder involving both tubules and glomeruli. Defects in this gene are also associated with Senior-Loken syndrome type 1, also referred to as juvenile nephronophthisis with Leber amaurosis, which is characterized by kidney and eye disease, and with Joubert syndrome type 4, which is characterized by cerebellar ataxia, oculomotor apraxia, psychomotor delay and neonatal breathing abnormalities, sometimes including retinal dystrophy and renal disease. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

NPHP1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.044297397).

BS1

Variant frequency is greater than expected in population eas. gnomad4_exome allele frequency = 0.000123 (180/1461836) while in subpopulation EAS AF= 0.00426 (169/39700). AF 95% confidence interval is 0.00373. There are 0 homozygotes in gnomad4_exome. There are 99 alleles in male gnomad4_exome subpopulation. Median coverage is 31. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NPHP1	NM_001128178.3 linkuse as main transcript	c.1861G>C	p.Glu621Gln	missense_variant	20/20	ENST00000445609.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NPHP1	ENST00000445609.7 linkuse as main transcript	c.1861G>C	p.Glu621Gln	missense_variant	20/20	1	NM_001128178.3	P2	O15259-2

Frequencies

GnomAD3 genomes

AF:

0.0000460

AC:

AN:

152206

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00135

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000143

AC:

AN:

251488

Hom.:

AF XY:

0.000162

AC XY:

AN XY:

135916

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00163

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.000489

GnomAD4 exome

AF:

0.000123

AC:

180

AN:

1461836

Hom.:

Cov.:

AF XY:

0.000136

AC XY:

AN XY:

727232

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00426

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.000149

GnomAD4 genome

AF:

0.0000460

AC:

AN:

152206

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74348

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00135

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000868

Hom.:

Bravo

AF:

0.0000604

ExAC

AF:

0.000115

AC:

Asia WGS

AF:

0.000866

AC:

AN:

3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Senior-Loken syndrome 1

Uncertain:1

Uncertain significance, 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 did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 20, 2021

The c.2029G>C (p.E677Q) alteration is located in exon 20 (coding exon 20) of the NPHP1 gene. This alteration results from a G to C substitution at nucleotide position 2029, causing the glutamic acid (E) at amino acid position 677 to be replaced by a glutamine (Q). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Nephronophthisis 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

Nephronophthisis

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 16, 2022

This sequence change replaces glutamic acid, which is acidic and polar, with glutamine, which is neutral and polar, at codon 677 of the NPHP1 protein (p.Glu677Gln). This variant is present in population databases (rs780427871, gnomAD 0.2%). This missense change has been observed in individual(s) with nephronophthisis and Bardet-Biedl syndrome (PMID: 27491411, 28624958). ClinVar contains an entry for this variant (Variation ID: 216416). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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. -

Joubert syndrome with renal defect

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Nov 06, 2017

- -

Joubert syndrome with renal defect;C1855681:Nephronophthisis 1;C4551559:Senior-Loken syndrome 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Feb 22, 2022

- -

not specified

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

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

Aug 23, 2022

Variant summary: NPHP1 c.2029G>C (p.Glu677Gln) results in a conservative amino acid change in 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 0.00014 in 251488 control chromosomes, predominantly at a frequency of 0.0016 within the East Asian subpopulation in the gnomAD database. The observed variant frequency within East Asian control individuals in the gnomAD database is approximately 3-fold of the estimated maximal expected allele frequency for a pathogenic variant in NPHP1 causing Joubert Syndrome And Related Disorders (0.00056), suggesting that the variant may be a benign polymorphism found primarily in populations of East Asian origin. c.2029G>C has been reported in the literature in the heterozygous state in settings of WES and multigene panel testing primarily in East Asian individuals affected with disorders related to Joubert syndrome, including retinitis pigmentosa and nephronophthisis, without strong evidence for causality (e.g. Fu_2013, Katagiri_2014, Sugimoto_2016, Kang_2016, Mori_2017, Qi_2017, Luo_2020). These report(s) do not provide unequivocal conclusions about association of the variant with Joubert syndrome and related disorders. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and all classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as likely benign. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.20

BayesDel_addAF

Benign

-0.21

BayesDel_noAF

Benign

-0.090

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.27

.;.;T;.;T

Eigen

Uncertain

0.62

Eigen_PC

Uncertain

0.55

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.91

D;D;D;D;D

M_CAP

Benign

0.072

MetaRNN

Benign

0.044

T;T;T;T;T

MetaSVM

Uncertain

0.052

MutationAssessor

Uncertain

2.7

.;.;M;.;.

MutationTaster

Benign

1.0

D;D;D;D;D

PrimateAI

Benign

0.40

PROVEAN

Benign

-1.2

N;N;N;N;N

REVEL

Benign

0.21

Sift

Uncertain

0.018

D;D;D;D;D

Sift4G

Uncertain

0.0070

D;D;D;D;D

Polyphen

1.0

D;D;D;D;.

Vest4

0.21

MutPred

0.34

.;.;Loss of disorder (P = 0.0799);.;.;

MVP

0.88

MPC

0.44

ClinPred

0.16

GERP RS

5.5

Varity_R

0.19

gMVP

0.34

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

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over