Coffin-Siris syndrome

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Coffin-Siris syndrome

ORPHA:1465Malformation syndrome

Also called CSS

What it is

A rare genetic syndromic intellectual disability of broad phenotypic range characterized by developmental delay and variable clinical features which most commonly, but not consistently, include aplasia or hypoplasia of the distal phalanx or nail of the fifth digit, and coarse facial features.

Key facts

Prevalence
<1 / 1 000 000
Age of onset
Antenatal, Neonatal
Inheritance
Autosomal dominant
Classified as
Malformation syndrome

Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.

Signs and symptoms

These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.

Genes

ARID1ADisease-causing germline mutation(s)
ARID1BDisease-causing germline mutation(s)
ARID2Disease-causing germline mutation(s) (loss of function)
DPF2Disease-causing germline mutation(s)
SMARCA4Disease-causing germline mutation(s)
SMARCB1Disease-causing germline mutation(s)
SMARCC2Disease-causing germline mutation(s)
SMARCD1Disease-causing germline mutation(s)
SMARCE1Disease-causing germline mutation(s)
SOX11Disease-causing germline mutation(s)
SOX4Disease-causing germline mutation(s)

ICD-10 codes

Q87.1filed under a broader ICD-10 category — shared with 107 other rare diseases

ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.

Related health topics

Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.

Cross-references

GARD 6124MEDDRA 10083941MESH C536436MONDO 0015452OMIM 135900OMIM 614607OMIM 614608OMIM 614609OMIM 615866OMIM 616938OMIM 617808OMIM 618027OMIM 618362OMIM 618506OMIM 618779OMIM 619325UMLS C0265338

Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.

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