15q11.2 BP1-BP2 Deletion

Below is a summary for 15q11.2 BP1-BP2 Deletions observed in research publications. This is not meant to take the place of medical advice.

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What is 15q11.2 BP1-BP2 microdeletion syndrome or Burnside-Butler Syndrome?

Chromosome 15q11.2 BP1-BP2 microdeletion syndrome can affect the development of communication, social, and learning skills. It can affect how a person acts or interacts with others. Many people who have chromosome 15q11.2 BP1-BP2 microdeletion syndrome have:

  • Developmental delay
  • Language delay
  • Memory issues
  • Less commonly – autism, seizures, and changes in facial features

The syndrome is also known as Burnside-Butler Syndrome.

What causes 15q11.2 BP1-BP2 microdeletion syndrome?


Chromosome 15q11.2 BP1-BP2 microdeletion syndrome is a rare condition caused when a small piece of DNA is missing from chromosome 15, one of the body’s 46 chromosomes.

Some people inherit a gene change from a parent. In other people, small mistakes can happen when genes are being copied. Parts of the chromosomes can break off, make extra copies, or end up in a different order than expected. When this happens, it is called a “de novo”, or new, change. The child can be the first in the family to have the gene change.

Do all people with 15q11.2 BP1-BP2 microdeletion syndrome have symptoms?

Not necessarily. Some people do not have any symptoms. Some people may not learn that they have this chromosome change until it is found in their children.

How many people have 15q11.2 BP1-BP2 microdeletion syndrome?

As of 2019, doctors had found about 200 people in the world with chromosome 15q11.2 BP1-BP2 microdeletion syndrome. The first case was found in 2007. Scientists expect to find more people who have the syndrome as access to genetic testing improves.

Do people with 15q11.2 BP1-BP2 microdeletion syndrome look different?

People who have chromosome 15q11.2 BP1-BP2 microdeletion syndrome may look different from others. Appearance can vary among people who have the syndrome. One study of almost 150 people found that about 40 percent have changes in facial features. These include a broad forehead, an unusual ear shape, and changes to the roof of the mouth, also called the palate.


About 67 percent of children who have the syndrome have speech delays.



About 60 percent have issues with reading, writing, and memory.



About 26 percent have seizures. About 24 percent have a small head.



Support Resources



GeneReviews are a great resource to bring to your child’s clinicians. These publications provide a summary of current research on genetic conditions and information on ongoing care.

There is currently no GeneReviews for 15q11.2 BP1-BP2 Deletion.


Research Article Summaries

We currently do not have any article summaries for 15q11.2 BP1-BP2 Deletion, but we add resources to our website as they become available.

The information available about 15q11.2 BP1-BP2 Deletion is limited, and families and doctors share a critical need for more information. As we learn more from children who have this gene change, we expect our list of resources and information to grow.

Full versions of published research articles can be found on PubMed. PubMed is a National Institutes of Health (NIH) online database that is free. It has a collection of both medical and scientific research articles. A PubMed search for 15q11.2 BP1-BP2 Deletion articles can be found here.


Research Opportunities

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Help the Simons Searchlight team learn more about 15q11.2 BP1-BP2 Deletion genetic changes by taking part in our research. You can learn more about the project and sign up here.


Family Stories

Stories from 15q11.2 BP1-BP2 deletion families:


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