World Down Syndrome Day

What Is World Down Syndrome Day?

Every March 21st is "World Down Syndrome Day." Established in 2004 by Down Syndrome International (DSI), based in the United Kingdom, and observed since 2006, it was adopted as an international day by the UN General Assembly in December 2011 and has been an official UN observance since 2012. The date, "3/21," reflects the fact that most people with Down syndrome have three copies of chromosome 21 instead of the usual two. It is a day for awareness activities around the world aimed at a society where people with Down syndrome can live safely and as themselves.

What Is Down Syndrome?

Down syndrome is a congenital condition caused by a difference in chromosomes, and it can occur in anyone.

• Origin of the name: It is named after John Langdon Down, the British physician who described the syndrome in 1866.
• Chromosomal features: In most cases it results from having three copies of chromosome 21 (trisomy 21). Common features include lower muscle tone and slower development, but the degree varies from person to person.

Wider Participation in Society

With advances in medical care and support, the lives of people with Down syndrome have changed greatly.

• Longer life expectancy: Thanks to medical progress and other factors, life expectancy has risen greatly, and many people now live beyond 60.
• Active in many fields: More and more people with Down syndrome are active in fields such as the arts, sports and work.

Fun Facts About World Down Syndrome Day

• Mismatched socks: On this day, the "Lots of Socks" campaign, in which people wear mismatched socks, takes place around the world. Socks are said to resemble the shape of chromosomes, and they serve as a symbol of accepting differences.
• An annual theme: Down Syndrome International sets a theme each year; in 2024 it was "End The Stereotypes."
• Frequency: Babies with Down syndrome are said to be born at a rate of roughly 1 in 800 to 1,000.
• Events in Japan: In Japan, the Japan Down Syndrome Society (JDS) and others hold talk events, photo exhibitions and landmark light-ups.

Tips for Marking World Down Syndrome Day

• Wear mismatched socks and join the campaign
• Learn accurate information from the websites of support groups such as the Japan Down Syndrome Society
• Explore films, books or artwork featuring people with Down syndrome
• Think about how to make your workplace or community easier for everyone to take part in

Toward a Society Where We Understand Differences and Live Together

World Down Syndrome Day is a day to learn accurately about Down syndrome and to think about a society that respects each person's individuality. On March 21st, why not use mismatched socks as a starting point to talk about "differences" with the people around you?