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International 15q Day

November 12, 2021

International 15q Day

15th chromosome with areas 11 - 13 pointed out
click to enlarge

November 15th is International 15q Day. 

Angelman, Prader-Willi, and Dup15q syndromes are all distinct neurodevelopmental disorders that are caused by changes within the specific q11 to q13 region of chromosome 15 (called 15q).

This region contains a number of important genes. Unlike most other genes in the body, these genes behave differently depending on whether they are on the copy from the mom (maternal) or from the dad (paternal); this is a biological mechanism called “genomic imprinting.”

  • Prader-Willi syndrome
    Occurs when the 15th chromosome from dad is missing information of the q11- q13 region
  • Angelman syndrome
    Occurs when the 15th chromosome from mom is missing information of the q11-q13 region
  • Dup15q syndrome
    Occurs when there is extra paternal or maternal q11-q13 information present on chromosome 15q


3 Ways to Raise Awareness of 15q Disorders

Angelman, Prader-Willi and Dup15q syndromes have high rates of misdiagnosis, simply because of lack of awareness. By spreading awareness, you are helping to reduce the rate of misdiagnosis for all three disorders and enhancing support for individuals living with each disorder.

  1. Enroll in LADDER.
  2. Wear blue and share this information.
  3. Create an All About Me Template (in Wordon Canva) for your individual to share with teachers, therapists or neighbors.

Shared Symptoms

Since Angelman, Prader-Willi and Dup15q syndromes are caused by changes in the 15th chromosome, there are symptoms that all three syndromes share. 



Collaboration Between Organizations

The ASF is proud to work with these organizations in efforts to advance research and improve the lives of those affected by 15th chromosome disorders. 

  • 15Q Clinical Research Network
    The ASF and Dup15q combined their respective clinic networks to provide individuals with AS and dup15q, comprehensive medical care they need throughout their lifetime as well as provide a foundation to support future clinical trials.  
  • LADDER (Linking Angelman and Dup15q Data for Expanded Research)
    A database that brings together information about Angelman and Dup15q syndromes, collected from sources all over the world. The information can be accessed by physicians, researchers and pharmaceutical partners who are working on drug development. 
  • Newborn Screening for Angelman syndrome, Prader-Willi, Fragile X and Dup15q syndromes
    This feasibility project tested a new diagnostic tool on 75,000 newborns with great accuracy.
  • Newborn Screening Grant for Early Check
    This is a co-funded project working to add Angelman syndrome, Dup15q and Prader-Willi syndrome to the newborn screening panel. 
  • Advancing Research
    The ASF and Dup15q cohost a Research Symposium every other year to bring together researchers and scientists studying Angelman syndrome and Dup15q AND have co-funded research projects to help advance the understanding of the genes and proteins of the 15th chromosome. 


Learn More About the Syndromes

You can learn more about Dup15q and Prader-Willi syndromes by visiting these organizations: