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Genetics Library / Conditions / SADDAN

CONDITION REFERENCE

SADDAN

Information from MedlinePlus Genetics about this condition and how it can be inherited.

About this condition

SADDAN (severe achondroplasia with developmental delay and acanthosis nigricans) is a rare disorder of bone growth characterized by skeletal, brain, and skin abnormalities.

All people with this condition have extremely short stature with particularly short arms and legs. Other features include unusual bowing of the leg bones; a small chest with short ribs and curved collar bones; short, broad fingers; and folds of extra skin on the arms and legs. Structural abnormalities of the brain cause seizures, profound developmental delay, and intellectual disability. Several affected individuals also have had episodes in which their breathing slows or stops for short periods (apnea). Acanthosis nigricans, a progressive skin disorder characterized by thick, dark, velvety skin, is another characteristic feature of SADDAN that develops in infancy or early childhood.

Source: MedlinePlus, National Library of Medicine. Source publication: 2020-08-18. Source review: 2006-06.

Inheritance

  • Autosomal dominant

A condition can have several forms with different inheritance patterns. Each pattern may apply to a different gene or form of the condition.

Related genes

MedlinePlus lists these genes for this condition. Open a gene page to read any available ClinGen reviews and ClinVar records.

YOUR DNA FILE

What can your DNA file tell you?

Your DNA file only includes the positions your test checked and reported. Consumer DNA kits usually test selected positions. Sequencing files can also leave out positions that were not reported or where the test could not give a result.

A variant missing from your file does not mean you tested negative for it. A ClinVar classification applies to a particular variant and the condition or finding it was reported for. It does not apply to everyone with that gene. An uncertain finding cannot establish a diagnosis.

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Sources and dates

The source information on this page last changed on 2026-09-18.

MedlinePlus Source details

Open source record ↗

Source release: Fri, 18 Sep 2026 05:17:13 GMT
Source publication: 2020-08-18
Source review: 2006-06

SHA-256: fdc8bd614310c12718379cef6569962e5d0e791cecabcc355b53a72816ac263a

About the library sources · Latest validated release · Record 9428bf46800f