Chromosome 16p12.2-p11.2 deletion syndrome, 7.1- to 8.7-mb

Due to the rarity of the condition, there will likely not be a local support group. However, due to the internet, families are able to connect from across the country and even across the world.

One organization advocating for more research into this condition is The 16p12.2 Deletion Project run through Penn State University. They are currently in the process of building a support network of parents and affected individuals. More information about the lab can be found here. They are also recruiting for a research study. More information on this can be found here.

In this day of social media, many individuals connect with others through these sources, like Facebook. Currently, there is at least one page on Facebook dedicated to 16p12.2 microdeletion. You can find these types of pages by searching 16p12.2 on social media pages. Please note, these pages often have little medical provider oversight and sometimes might not have all the updated medical information. Other times, these pages are great places to find new potential research or clinical studies that become available. There is also another online community called "Circle of Moms" that has a group of families with 16p12.2 deletions (or similar). Their site can be accessed at: http://www.circleofmoms.com/unique-chromosome-abnormalities/chromosome-16-11-2-12-2-deletion-375384

A few other support resources include:

At www.simonsvipconnect.org there is an online community
for families affected by 16p11.2 deletions and duplications

At https://groups.yahoo.com/neo/groups/16pdeletion/info there is an on-line group for families affected by a 16p11.2 microdeletion.

Rare Chromosome Disorder Support Group at www.rarechromo.org

The types of healthcare providers needed will depend upon the health problems and/or developmental programs the child is experiencing. These different providers can be found at many health centers across the country.

If you are pregnant and your OB/GYN has noticed some findings on ultrasound, you’ll like be referred to a maternal fetal medicine (MFM) doctor. These doctors specialize in pregnancies that require special care and attention. You may be offered testing to confirm a diagnosis during pregnancy. It may also be necessary to see a medical genetics team. They can help explain the results of the genetic testing.

If no work-up is completed during the pregnancy, after birth the newborn will likely be evaluated by a geneticist. This is a doctor that specializes in genetic conditions. Blood work may be done to diagnose the condition. The newborn will then be followed by other medical specialists as needed. For example, if the newborn has a heart defect they will see a cardiologist – a doctor that specializes in the heart. If the infant experiences seizures, they’ll be seen by a neurologist.

Genetic counselors can also help to explain the condition to the family so they can better understand what to expect. Also, genetic counselors can help to explain how likely it is to happen again and if other family members would need to be tested.

16p12.2 microdeletion syndrome is a genetic condition caused when a small section of the DNA is missing between bands 12.2 and 11.2 on the "p" arm (short arm) of chromosome 16.
In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes named X and Y, differs between males and females and usually determines if we are a boy or girl. The numbered chromosomes are numbered 1-22, from largest to smallest. Each chromosome has 2 parts, called the long arm and the short arm. The long arm is referred to as "q" and the short arm is abbreviated "p". Both arms of all chromosomes are further divided into light and dark colored bands that are labeled by numbers. The further away from the centromere (connecting part between p and q arm) the higher the number. The labeled bands help everyone stay consistent in discussed specific parts of the chromosome.

In 16p12.2-p11.2 microdeletion syndrome the size of the missing piece can vary and so can the health problems that it causes. The health issues can include: developmental delay, intellectual disability, unique facial features, recurrent ear infections, feeding difficulties, seizures, behavioral problems, autism spectrum, heart defects, and shorter than average height.

Children with 16p12.2 microdeletion are at risk for having intellectual impariment, developmental delay, and/or speech delay. Because of these and other medical issues they may need additional support in school. You will need to meet with school officials to set up an Individual Education Plan (IEP) for any learning or medical concerns that may affect school performance. You can get useful information from the Understood website to help you navigate this process in your local schools.

Currently, there are no Centers of Excellence for those with 16p12.2 Microdeletion. This is because it is so rare. However, there is a group of physicians one will likely need and those can be found at many health centers across the country.

If you are pregnant and your OB/GYN has noticed some findings on ultrasound, you’ll like be referred to a maternal fetal medicine (MFM) doctor. These doctors specialize in pregnancies that require special care and attention. You may be offered testing to confirm a diagnosis during pregnancy. It may also be necessary to see a medical genetics team. They can help explain the results of the genetic testing.

If no work-up is completed during the pregnancy, after birth the newborn will likely be evaluated by a geneticist. This is a doctor that specializes in genetic conditions. Blood work may be done to diagnose the condition. The newborn will then be followed by other medical specialists as needed. For example, if the newborn has a heart defect they will see a cardiologist – a doctor that specializes in the heart. If the infant experiences seizures, they’ll be seen by a neurologist.

Genetic counselors can also help to explain the condition to the family so they can better understand what to expect. Also, genetic counselors can help to explain how likely it is to happen again and if other family members would need to be tested.

16p12.2 microdeletion syndrome is a genetic condition caused when a small section of the DNA is missing between bands 12.2 and 11.2 on the "p" arm (short arm) of chromosome 16.

In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes named X and Y, differs between males and females and usually determines if we are a boy or girl. The numbered chromosomes are numbered 1-22, from largest to smallest. Each chromosome has 2 parts, called the long arm and the short arm. The long arm is referred to as "q" and the short arm is abbreviated "p". Both arms of all chromosomes are further divided into light and dark colored bands that are labeled by numbers. The further away from the centromere (connecting part between p and q arm) the higher the number. The labeled bands help everyone stay consistent in discussed specific parts of the chromosome.

When a small section of our DNA is missing, it means that some of the genes that guide human growth and function are missing. Missing genes lead to health problems.

Usually, the word "variant" in regards to genetics is reserved for a change within a gene. Genes are smaller parts of the larger chromosome and contain instructions for our body’s growth and development. With 16p12.2 microdeletion, there are not variants in the gene. Instead genes are deleted because parts of the chromosome has been deleted. The missing copy of the genes is what causes the problems associated with 16p12.2

The main symptoms and features of 16p12.2 microdeletion syndrome vary greatly based upon exactly what genetic information are missing. As a very limited number of children/adults have been reported with identical break points (where missing section starts and stops), it is very challenging to provide a list of symptoms for all people with deletions. What is provided below are the most common health problems been reported in children and adults with 16p12.2 microdeletion, not specific to certain break points.

Developmental delay, speech delay, intellectual disability, craniofacial or skeletal features, growth retardation (slow growth), microcephaly (smaller head size), congenital heart defects, epilepsy (seizures), psychiatric/behavioral disorders, feeding difficulties in infancy, recurrent ear infections, hearing loss, hypotonia (low muscle tone), and sacral dimple or tethered cord (spinal cord defects),

According to GeneReviews, there are several different recommended steps after someone receives a diagnosis of 16p12.2 microdeletion syndrome. These include:
To establish the extent of disease and needs of an individual diagnosed with the 16p12.2 microdeletion, the following evaluations are recommended:
– Clinical genetics consultation
– Measurement of height and weight
– Broad review of all organ systems
– Developmental assessment with cognitive and behavioral testing

Also consider:
– Consultation with a neurologist (brain doctor) and EEG testing if history suggests the possibility of seizures
– Evaluation and echocardiogram by a cardiologist (heart doctor)
-Consultation with a nephrologist (kidney doctor)
-Psychiatrist if there are psychiatric symptoms
-Dentist

If this information is new to your family, it may also be helpful to talk with a genetic counselor to learn if other people in your family need to be offered testing. Genetic counselors can also help discuss the chances of it happening again in another pregnancy.

There is variable expression in 16p12.2 microdeletion. This means that the symptoms of one person with this condition may vary from the symptoms of another person with this same condition. Also, because the symptoms vary based upon the exact breakpoints (starting and stopping of deleted material), there can be variability depending on the region deleted.
There is also reduced penetrance in 16p12.2 microdeletion, meaning that not everyone with this condition will show symptoms. There are reports of individuals that have the 16p12.2 microdeletion who have children with the same microdeletion and show symptoms. We do not completely understand why this happens.

As of June 2016, no states were currently offering a newborn screening that included 16p12.2 microdeletion.

Unless a child has been diagnosed with a 16p12.2 microdeletion and the doctors are testing the parents or other siblings, the doctors are not necessarily going to know that is what they are looking for. The features of 16p12.2 microdeletion are not specific to that disorder. Therefore, most of the time the doctors will be ordering a broad test, like a microarray to essentially look for any deleted or duplicated genetic information. This is usually accomplished through a blood test. It is then sent to a genetic testing laboratory to evaluate the DNA. The microarray is able to see "breakpoints" – where the deleted DNA starts or stops. This can be important to determine what genes (sections of DNA that contain instructions for our body to develop and function) are affected to better predict how the individual may be affected.

If a woman is pregnant, it is also possible to test the pregnancy through amniocentesis or Chorionic villus sampling. More information on how these procedures are done and the timing of when they are able to be completed during a pregnancy be found by clicking the above links.

As of June 2016, the Girirajan Lab out of Penn State was recruiting patients with 16p12.2 microdeletion to participate in a questionnaire study to learn more about the clinical variability of features associated with the syndrome. To learn more about the study and see if it is something you would be interested in, visit the link https://autism.bx.psu.edu/16p12.2/participate.html

Another good place to look for clinical trials or research studies is the ClinicalTrials.gov

There is no cure for 16p12.2 microdeletion syndrome. We are not able to replace the missing part of the DNA. Instead, infants, children and adults are managed based upon their symptoms. For example, if a child has is not meeting their milestones by the ages they should, they would be enrolled in early intervention to help them develop and progress. If a child has a heart problem, the will be managed like any other child who has that heart problem. The same is true for any other health concerns the individual has.
As with any health condition, early detection and treatment is key to having the most positive outcome.

It is not fully known how many people may have the 16p12.2 microdeletion. This is because we don’t routinely look for the change in average people. Reported incidences of people with the 16p12.2 microdeletion vary from 1 in 1,400 to 1 in 15,000 babies born alive.

Life expectancy is usually not shortened for those with 16p12.2 microdeletion syndrome. However, some children are born with heart defects and depending on the severity, this could be a health risk. The epilepsy/seizures can also be a significant health risk depending on severity.

There is no treatment specific to 16p12.2 microdeletion syndrome. Instead, infants, children and adults are managed based upon their symptoms. For example, if a child has is not meeting their milestones by the ages they should, they would be enrolled in early intervention to help them develop and progress. If a child has a heart problem, the will be managed like any other child who has that heart problem. The same is true for any other health concerns the individual has.
As with any health condition, early detection and treatment is key to having the most positive outcome.

It is estimated about 95% of the time, a child will inherit the 16p12.2 microdeletion from either of their parents. We receive one chromosome 16 from our mother and one chromosome 16 from our father. If a parent has the 16p12.2 microdeletion, there is a 50/50 chance (1 in 2) for it to be passed on with each pregnancy – this is regardless of gender of the parent or gender of the father. This is termed autosomal dominant inheritance.

It is estimated about 3.5-5% of the time neither parent carries the microdeletion and it is new to the child. This is termed de novo and happens when the child is conceived. We cannot assume it is a de novo mutation just because a parent doesn’t have the same symptoms as the child. This is because some people with the 16p12.2 microdeletion have no signs or symptoms due to reduced penetrance. We do not fully understand why this happens. Because of this, when a child is diagnosed with a 16p12.2 microdeletion, it is important to try and test the parents so we can properly educate them on the risk for it to happen in a future pregnancy.

Unless a child has been diagnosed with a 16p12.2 microdeletion and the doctors are testing the parents or other siblings, the doctors are not necessarily going to know that is what they are looking for. The features of 16p12.2 microdeletion are not specific to that disorder. Therefore, most of the time the doctors will be ordering a broad test, like a microarray to essentially look for any deleted or duplicated genetic information. This is usually accomplished through a blood test. It is then sent to a genetic testing laboratory to evaluate the DNA. The microarray is able to see "breakpoints" – where the deleted DNA starts or stops. This can be important to determine what genes (sections of DNA that contain instructions for our body to develop and function) are affected to better predict how the individual may be affected.

If a woman is pregnant, it is also possible to test the pregnancy through amniocentesis or Chorionic villus sampling. More information on how these procedures are done and the timing of when they are able to be completed during a pregnancy be found by clicking the above links.

As of June 2016, the Girirajan Lab out of Penn State was recruiting patients with 16p12.2 microdeletion to participate in a questionnaire study to learn more about the clinical variability of features associated with the syndrome. To learn more about the study and see if it is something you would be interested in, visit the link https://autism.bx.psu.edu/16p12.2/participate.html

Other placed to look for current clinical trials or research studies include the following.

16p12.2 microdeletion is also known as 16p11.2-p12.2 deletion or 16p12.1 microdeletion. Please note that these may describe slightly different conditions. The numbers describe exactly what points are missing along the p arm of chromsome 16 and therefore exactly what genes are missing. This can help to provide some information to the family as to what they can expect.

The differential diagnosis for 16p12.2 microdeletion is broad, including many causes of developmental delays and/or behavior abnormalities, which are frequently difficult to distinguish without genetic testing. Therefore, microarray will likely to done to determine the diagnosis.

Due to the rarity of the condition, there will likely not be a local support group. However, due to the internet, families are able to connect from across the country and even across the world.

One organization advocating for more research into this condition is The 16p12.2 Deletion Project run through Penn State University. They are currently in the process of building a support network of parents and affected individuals. More information about the lab can be found here. They are also recruiting for a research study. More information on this can be found here.

In this day of social media, many individuals connect with others through these sources, like Facebook. Currently, there is at least one page on Facebook dedicated to 16p12.2 microdeletion. You can find these types of pages by searching 16p12.2 on social media pages. Please note, these pages often have little medical provider oversight and sometimes might not have all the updated medical information. Other times, these pages are great places to find new potential research or clinical studies that become available. There is also another online community called "Circle of Moms" that has a group of families with 16p12.2 deletions (or similar). Their site can be accessed at: http://www.circleofmoms.com/unique-chromosome-abnormalities/chromosome-16-11-2-12-2-deletion-375384

A few other support resources include:

At www.simonsvipconnect.org there is an online community for families affected by 16p11.2 deletions and duplications

At https://groups.yahoo.com/neo/groups/16pdeletion/info there is an on-line group for families affected by a 16p11.2 microdeletion.

Rare Chromosome Disorder Support Group at www.rarechromo.org

Everyone with 16p12.2 microdeletion has it due to a missing section of DNA on their short arm (p arm) of chromosome 16. This causes some of our genetic information to be deleted – hence it is always genetic. However, just because it is genetic doesn’t mean it is always inherited from a parent. Sometimes, it is new to that child.