Legius syndrome
Findings
No curated finding names Legius syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Legius syndrome, also known as NF1-like syndrome, is a rare, genetic skin pigmentation disorder characterized by multiple cafC)-au-lait macules with or without axillary or inguinal freckling.
Definition from the Mondo Disease Ontology (MONDO:0012669), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal dominant inheritance
HPO, annotations 2026-09-02
Features
41 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Cafe-au-lait spotHPOHP:0000957
- 62 of 62 reported patients
- Multiple cafe-au-lait spotsHPOHP:0007565
- Very frequent (80% to 99% of cases)
- Atypical behaviorHPOHP:0000708
- Frequent (30% to 79% of cases)
- Axillary frecklingHPOHP:0000997
- 10 of 18 reported patients
- Frequent (30% to 79% of cases)
- Inguinal frecklingHPOHP:0030052
- 9 of 18 reported patients
- Frequent (30% to 79% of cases)
- Specific learning disabilityHPOHP:0001328
- Frequent (30% to 79% of cases)
Show the remaining 29
- FrecklingHPOHP:0001480
- 14 of 43 reported patients
- Acute monocytic leukemiaHPOHP:0004845
- Very rare (1% to 4% of cases)
- Attention deficit hyperactivity disorderHPOHP:0007018
- 2 of 40 reported patients
- Very rare (1% to 4% of cases)
- Brain imaging abnormalityHPOHP:0410263
- Very rare (1% to 4% of cases)
- CataractHPOHP:0000518
- Very rare (1% to 4% of cases)
- Chiari type I malformationHPOHP:0007099
- Very rare (1% to 4% of cases)
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- SPRED1HGNC:20249
- Definitive · Ambry Genetics · Autosomal dominant · 2018
- Definitive · ClinGen · Autosomal dominant · 2019
- Definitive · G2P · Autosomal dominant · 2015
- Strong · Genomics England PanelApp · Autosomal dominant · 2020
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2020
- Strong · PanelApp Australia · Autosomal dominant · 2025
- Supportive · Orphanet · Autosomal dominant · 2021
Where it sits
Other names
2 names
Resolves to: Legius syndrome
- Also called
- neurofibromatosis 1-like syndromeNF1-like syndrome