Down syndrome

Congenital disorder caused by an extra chromosome (trisomy) on the chromosome 21 pair. Those with the syndrome may have broad, flat faces; up-slanted eyes, sometimes with epicanthal folds (whence its former name, mongolism); intellectual disability (usually moderate); heart or kidney malformations; and abnormal fingerprint patterns. Many persons with Down syndrome can live and work independently or in a sheltered environment, but they age prematurely and have a short (55-year) life expectancy. The risk of bearing a child with the disorder increases with the mother's age; it can be detected in the fetus by amniocentesis.

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Events

By place

Roman Empire

• Revolt of the Aedui under Julius Florus and Julius Sacrovir, suppressed by Gaius Silius.
• Tiberius is a Roman Consul for the fourth time.
• Beginning of the revolt in Africa led by Tacfarinas.
• The Romans create a buffer state in the territory of the Quadi in southern Slovakia.
• A barracks is constructed for the Praetorian Guard on the Quirinal.

Asia

• King Daeso of Dongbuyeo is killed in battle against the armies of Goguryeo, led by its third ruler, King Daemusin.

By topic

Arts and Sciences

• Manufacture of pens and metal writing tools in Rome.

Births

Deaths

• Publius Sulpicius Quirinius, Roman governor of Syria
• Marcus Valerius Messalla Barbatus, Roman Consul (or 20)
• Arminius, Germanic leader who killed three Roman legions at the Battle of the Teutoburg Forest
• Empress Wang