Is NPHP4 p.Pro1222Ala (c.3664C>G) pathogenic?

NPHP4 p.Pro1222Ala (c.3664C>G) is classified Uncertain significance in NPHP4 (ClinVar, Multiple submitters, 3 submitters; last evaluated 2024-03-07). AlphaMissense: likely benign (0.1952); Very rare (popmax 0.00251%, nfe); Associated with nephronophthisis.

What condition is associated with NPHP4 p.Pro1222Ala (c.3664C>G)?

NPHP4 p.Pro1222Ala (c.3664C>G) is associated with nephronophthisis, nephronophthisis 4, Senior-Loken syndrome 4 (ClinVar).

How common is NPHP4 p.Pro1222Ala (c.3664C>G) in the general population?

NPHP4 p.Pro1222Ala (c.3664C>G) is very rare (popmax 0.00251%, nfe) (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 NPHP4 p.Pro1222Ala (c.3664C>G)?

AlphaMissense predicts likely benign (score 0.1952) — an in-silico prediction, not a clinical call.

NPHP4 p.Pro1222Ala

c.3664C>G · rs1038494626 · VCV1522095

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

AlphaMissense

likely benign

0.1952 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00251%, nfe)

Missense predictors

0/2 damaging

AlphaMissense, SaProt · REVEL no call

Conditions

nephronophthisis

Computational evidence

Protein change
AlphaMissense	0.1952	likely benign
REVEL	0.495	indeterminate
SaProt	LLR -8.71	tolerated
⇒ AlphaMissense and SaProt both call this tolerated; REVEL makes no call.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 12	GERP 1.8, phastCons 1
Regional constraint	o/e 1.02	unconstrained · MANE · 123 kb · p 0.49 · regional, not allelic
Overall
CADD	23.6	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — a triage signal, not a reclassification

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

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00251% European (non-Finnish) · 29/1,153,880 alleles

Filtering AF 0.00176% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00152%

Overall 0.00203% 32/1,575,512 alleles · very rare exomes 29/1,423,280 · genomes 3/152,232 · joint denominator

Ancestry group	Frequency	1 in
Remaining individualsnot grpmax-eligible	0.0033%	30,338
European (non-Finnish)grpmax	0.00251%	39,789
African / African-American	0.00135%	74,238

Remaining individuals shows a higher raw frequency than the grpmax group above it. gnomAD excludes bottlenecked groups — Finnish, Ashkenazi Jewish, Amish and “Remaining individuals” — from grpmax, because founder effects make their frequencies unrepresentative for filtering. The table is sorted by frequency, so an excluded group can sit above the grpmax row.

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: NPHP4
Protein: p.Pro1222Ala
Coding: c.3664C>G
MANE Select: NM_015102
dbSNP: rs1038494626
Type: single nucleotide variant
Location: chr1:5865254 (GRCh38)
Gene constraint: LOEUF 1.183 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 72.44
Residue 1222: the 'sufficient for basal bodies localization' region

Full NPHP4 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

Also linked: nephronophthisis 4 Senior-Loken syndrome 4

For Nephronophthisis (Orphanet):

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

Similar variants

NPHP4 c.2304+1G>A Pathogenic ★★ same condition
NPHP4 c.2611+1G>A Pathogenic/Likely pathogenic ★★ same condition
NPHP4 c.2611+1G>C Pathogenic ★★ same condition
NPHP4 c.3644+1G>A Pathogenic/Likely pathogenic ★★ same condition
NPHP4 c.3644+1G>T Pathogenic/Likely pathogenic ★★ same condition
NPHP4 c.517+1G>A Pathogenic/Likely pathogenic ★★ same condition
NPHP4 c.518-2A>G Likely pathogenic ★★ same condition
NPHP4 c.992+2T>C 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/nphp4-p-pro1222ala (accessed [today's date]).

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