Most people have 23 pairs of chromosomes in most or all of their cells for a total of 46 chromosomes in all. These chromosomes include DNA and other material that provide a blueprint for “building” a person.
Some people have trisomy conditions—those related to having an extra chromosome in most or all of their cells, for a total of 47 chromosomes in all.
An extra chromosome can cause a variety of health problems ranging from mild intellectual and developmental disability (IDD), to severe physical problems.
During Trisomy Awareness Month in March, the NICHD joins other agencies and organizations in raising awareness about trisomy conditions and the challenges they may pose to individuals and families. Research on these conditions—from their origins, to their mechanisms, to their treatments—plays an important role in the lives of these individuals and families. Select a link below to learn more about trisomy conditions and NICHD research.
About Trisomy ConditionsDown Syndrome ConsortiumOther NICHD ActivitiesMore Information
Trisomy occurs when a person has a full or partial extra chromosome in most or all of his or her cells—47 chromosomes total.
The specific health issues of a trisomy condition and how severe those issues are depend on:
Health conditions and problems associated with trisomy include physical abnormalities, such as extra fingers or toes; physiological issues, such as irregular heartbeat patterns; and problems related to intellectual and developmental functioning.
Most of the time, trisomy conditions are not passed from one generation to the next, but result from a random error that occurs during cell division very early on in development.
Trisomy can occur with any chromosome, but the most well-known syndromes are:
NICHD efforts related to Down syndrome have been ongoing since the Institute was established in 1962. NICHD research on Down syndrome includes intramural scientists at the NICHD and extramural researchers who study Down syndrome at other institutions and universities with support from the NICHD.
In 2011, the NICHD led members of the NIH Down Syndrome Working Group, other agencies, and national Down syndrome organizations in forming the Down Syndrome Consortium. This Consortium is a public-private collaboration that focuses on implementing the NIH Research Plan on Down Syndrome, a comprehensive blueprint for NIH Down syndrome research efforts that was drafted in 2007.
The Consortium recently launched a website—http://downsyndrome.nih.gov—to provide a central portal for addressing research needs, communicating research findings, and accessing resources related to Down syndrome, including the National Down Syndrome Patient Registry.
Establishment of a National Down Syndrome Patient Registry was a primary recommendation of the 2007 Research Plan. The Registry, which is anticipated to launch in July 2013, will facilitate communication and information sharing among families, patients, researchers, and parent groups. It will also encourage data collection for research biorepositories and will make it easier for patients to take part in clinical studies on Down syndrome. For more information, visit http://downsyndrome.nih.gov/registry/Pages/default.aspx.
The Institute also supports the following projects related to trisomy conditions.
The Institute remains dedicated to understanding trisomy conditions as a way to help individuals and families live longer, healthier lives.
For more information about trisomy research, select one of the following links:
Originally Posted: March 15, 2013
All NICHD Spotlights