Is NPHP1 p.Asn77Lys (c.231C>G) pathogenic?

NPHP1 p.Asn77Lys (c.231C>G) is classified Uncertain significance in NPHP1 (ClinVar, Single submitter, 1 submitter; last evaluated 2022-03-03). AlphaMissense: ambiguous (0.41); Absent from gnomAD v4.1; Associated with nephronophthisis.

What condition is associated with NPHP1 p.Asn77Lys (c.231C>G)?

NPHP1 p.Asn77Lys (c.231C>G) is associated with nephronophthisis (ClinVar).

How common is NPHP1 p.Asn77Lys (c.231C>G) in the general population?

NPHP1 p.Asn77Lys (c.231C>G) is absent from gnomAD v4.1 (gnomAD).

How is Nephronophthisis inherited?

Typically Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

What do computational predictors say about NPHP1 p.Asn77Lys (c.231C>G)?

AlphaMissense predicts ambiguous (score 0.41) — an in-silico prediction, not a clinical call.

NPHP1 p.Asn77Lys

c.231C>G · rs1373708368 · VCV943367

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

ambiguous

0.41 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

0/2 damaging

REVEL, SaProt · AlphaMissense indeterminate

Conditions

nephronophthisis

Computational evidence

Protein change
AlphaMissense	0.41	ambiguous
REVEL	0.193	benign-leaning
SaProt	LLR -7.52	tolerated
⇒ REVEL and SaProt both call this tolerated; AlphaMissense is indeterminate.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 1.4	GERP 0.83, phastCons 1
Regional constraint	o/e 0.96	unconstrained · MANE · 81 kb · p 0.26 · regional, not allelic
Overall
CADD	19.82	PHRED · no single calibrated threshold — expert panels disagree

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

Population frequency

gnomAD v4.1 · exomes + genomes

Absent from gnomAD v4.1. Not observed in any sequenced alleles — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.

Variant & gene context

Gene: NPHP1
Protein: p.Asn77Lys
Coding: c.231C>G
MANE Select: NM_001128178
dbSNP: rs1373708368
Type: single nucleotide variant
Location: chr2:110178521 (GRCh38)
Gene constraint: LOEUF 0.92 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 76.22 · 2 PDB
Residue 77: an α-helix

Full NPHP1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

nephronophthisis — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Nephronophthisis (Orphanet):

Inheritance: Autosomal recessive
Onset: Adolescent, Adult, Antenatal, Childhood, Infancy, Neonatal
Prevalence: 1-9 / 100 000 (Finland)

Similar variants

NPHP1 p.Asn77= Likely benign ★ same residue
NPHP1 c.1270-1G>A Pathogenic ★★ same condition
NPHP1 c.1270-2A>G Pathogenic/Likely pathogenic ★★ same condition
NPHP1 c.143+1G>C Likely pathogenic ★★ same condition
NPHP1 c.144-1G>A Pathogenic/Likely pathogenic ★★ same condition
NPHP1 c.1716+1G>T Pathogenic/Likely pathogenic ★★ same condition
NPHP1 c.329+1G>A Pathogenic/Likely pathogenic ★★ same condition
NPHP1 c.522+1G>A Likely pathogenic ★★ same condition

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/nphp1-p-asn77lys (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown