raremaprare-disease reference indexOrphadata 2026-06-23 · HPO 2026-09-01
ORPHA:56304

Atelosteogenesis type II

Synonyms: AO2 · AOII · Atelosteogenesis type 2 · De la Chapelle dysplasia · Neonatal osseous dysplasia type 1

Type
Malformation syndrome
Group
Disorder
Inheritance
Autosomal recessive
Age of onset
Infancy, Neonatal
Status
active

A rare, lethal perinatal bone dysplasia characterized by limb shortening, normal sized skull with cleft palate, hitchhiker thumbs, distinctive facial dysmorphism and radiographic skeletal features, caused by mutations in the diastrophic dysplasia sulfate transporter gene.

1

Names in Orphadata languages

12 of 12 languages
LangNameSynonyms
enAtelosteogenesis type IIAO2 · AOII · Atelosteogenesis type 2 · De la Chapelle dysplasia · Neonatal osseous dysplasia type 1
frAtélostéogenèse type IIAO2 · AOII · Atélostéogenèse type 2 · Chondrodysplasie létale type de la Chapelle · Dysplasie osseuse néonatale type 1
deAtelosteogenesis Typ IIAO2 · AOII · Atelosteogenesis Typ 2 · Dysplasie Typ De-la-Chapelle · Dysplasie, neonatale ossäre, Typ 1
esAtelosteogénesis tipo IIDisplasia de la Chapelle · Displasia ósea neonatal tipo 1 · AO2 · AOII · Atelosteogénesis tipo 2
itAtelosteogenesi 2Displasia di De la Chapelle · Displasia ossea neonatale 1
nlAtelosteogenese type IIAO2 · AOII · Atelosteogenese type 2 · Dysplasie, De la Chapelle-type · Neonatale ossale dysplasie type 1
ptAtelosteogénese IIDisplasia de la Chapelle · Displasia óssea neonatal 1
plAtelosteogeneza typu IIAO2 · AOII · Atelosteogeneza typu 2 · Dysplazja De la Chapelle · Noworodkowa dysplazja kości typu 1
csAtelosteogeneze, typ IIAtelosteogeneze, typ 2 · De la Chapellova dysplázie · Neonatální oseální dysplázie, typ 1
ukАтелостеогенез, тип IIAO2 · AOII · Ателостеогенез типу 2 · Дисплазія де ла Шапель · Неонатальна кісткова дисплазія типу 1
zh成骨不全II型新生儿骨发育不良1型
trAtelosteogenez tip IIAO2 · AOII · Atelosteogenez tip 2 · De la Chapelle displazisi · Yenidoğan kemik displazisi tip 1

Definition in:

2

Cross-references

qualifier = Orphanet mapping relation
SourceCodeQualifierICD relationValidation
OMIM256050Evalidated
ICD-10Q77.5NTBTattributedvalidated
ICD-11LD24.03NTBTindexvalidated
MONDO0009727Evalidated
MeSHC535395Evalidated
UMLSC1850554Evalidated
GARD8329Evalidated

E exact · NTBT this ORPHAcode is narrower than the target · BTNT broader than the target · ND not decided.

3

Classification

Preferential parent (Orphanet linearisation):

Parents in the classifications (5):

No children.

Codes that Orphanet moved or referred to this one:

4

Genes

1 direct
GeneAssociationStatusHGNCEnsemblOMIMLocusNameSource of validation
SLC26A2Disease-causing germline mutation(s) inAssessedHGNC:10994ENSG000001558506067185q32solute carrier family 26 member 220301493[PMID]
5

Prevalence and incidence

2 records
TypeClassValueAreaQualificationValidationSource
Cases/families25 casesWorldwideCase(s)ValidatedORPHANET
Point prevalence<1 / 1 000 000—WorldwideClass onlyValidatedORPHANET

Value is Orphadata's ValMoy: the mean estimate per 100 000 for prevalence and incidence, the number of cases or families for case reports.

6

HPO phenotypes

53 annotations · validated 2019-03-26
HPOTerm (as annotated by Orphanet)Diagnostic
Very frequent (99-80%)
HP:0009826Limb undergrowth
Frequent (79-30%)
HP:0001999Abnormal facial shape
HP:0001591Bell-shaped thorax
HP:0001776Bilateral talipes equinovarus
HP:0001156Brachydactyly
HP:0001230Broad metacarpals
HP:0006009Broad phalanx
HP:0012385Camptodactyly
HP:0000175Cleft palate
HP:0006375Dumbbell-shaped femur
HP:0008110Equinovarus deformity
HP:0012427Excessive femoral anteversion
HP:0002857Genu valgum
HP:0001234Hitchhiker thumb
HP:0008752Laryngeal cartilage malformation
HP:0001602Laryngeal stenosis
HP:0001840Metatarsus adductus
HP:0000774Narrow chest
HP:0002089Pulmonary hypoplasia
HP:0008905Rhizomelia
HP:0004991Rhizomelic arm shortening
HP:0001852Sandal gap
HP:0003097Short femur
HP:0006385Short lower limbs
HP:0010049Short metacarpal
HP:0000470Short neck
HP:0009803Short phalanx of finger
HP:0000773Short ribs
HP:0005257Thoracic hypoplasia
HP:0003423Thoracolumbar kyphoscoliosis
HP:0100694Tibial torsion
HP:0002786Tracheobronchomalacia
HP:0001193Ulnar deviation of the hand or of fingers of the hand
HP:0009824Upper limb undergrowth
Occasional (29-5%)
HP:0100337Bilateral cleft palate
HP:0002947Cervical kyphosis
HP:0002987Elbow flexion contracture
HP:0000286Epicanthus
HP:0004664Facial midline hemangioma
HP:0000316Hypertelorism
HP:0008434Hypoplastic cervical vertebrae
HP:0000343Long philtrum
HP:0000369Low-set ears
HP:0000347Micrognathia
HP:0002983Micromelia
HP:0011800Midface retrusion
HP:0001357Plagiocephaly
HP:0001561Polyhydramnios
HP:0001538Protuberant abdomen
HP:0000506Telecanthus
HP:0000219Thin upper lip vermilion
HP:0012810Wide nasal base
Very rare (<4-1%)
HP:0003042Elbow dislocation

Run the differential on the 1 obligate / very frequent terms

Annotation source: 21077202[PMID]_20301493[PMID]

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Sources for this card